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| United States Patent Application |
20110244012
|
| Kind Code
|
A1
|
|
Iida; Hironori
;   et al.
|
October 6, 2011
|
FUNGICIDE, PHOTO CATALYTIC COMPOSITE MATERIAL, ADSORBENT, AND DEPURATIVE
Abstract
Disclosed herein is a fungicide, including: a porous carbon material; and
a silver member adhered to the porous carbon material, wherein a value of
a specific surface area based on a nitrogen BET, namely
Brunauer, Emmett, and Teller method is equal to or larger than 10
m.sup.2/g, and a volume of a fine pore based on a BJH, namely Barrett,
Joyner, and Halenda method and an MP, namely Micro Pore method is equal
to or larger than 0.1 cm.sup.3/g.
| Inventors: |
Iida; Hironori; (Kanagawa, JP)
; Yamanoi; Shun; (Kanagawa, JP)
; Minatoya; Machiko; (Tokyo, JP)
; Tabata; Seiichiro; (Kanagawa, JP)
; Yamada; Shinichiro; (Kanagawa, JP)
|
| Assignee: |
Sony Corporation
Tokyo
JP
|
| Serial No.:
|
053558 |
| Series Code:
|
13
|
| Filed:
|
March 22, 2011 |
| Current U.S. Class: |
424/409; 424/618; 502/182; 502/401 |
| Class at Publication: |
424/409; 424/618; 502/182; 502/401 |
| International Class: |
A01N 25/08 20060101 A01N025/08; A01N 59/16 20060101 A01N059/16; A01P 3/00 20060101 A01P003/00; B01J 21/18 20060101 B01J021/18; B01J 20/22 20060101 B01J020/22 |
Foreign Application Data
| Date | Code | Application Number |
| Mar 30, 2010 | JP | 2010-077883 |
| Jan 20, 2011 | JP | 2011-009456 |
Claims
1. A fungicide, comprising: a porous carbon material; and a silver member
adhered to said porous carbon material, wherein a value of a specific
surface area based on a nitrogen BET, namely Brunauer, Emmett, and Teller
method is equal to or larger than 10 m.sup.2/g, and a volume of a fine
pore based on a BJH, namely Barrett, Joyner, and Halenda method and an
MP, namely Micro Pore method is equal to or larger than 0.1 cm.sup.3/g.
2. The fungicide according to claim 1, wherein a silver member is
composed of either a particle containing therein silver, a silver alloy
or a silver ion, or a thin film containing therein silver, said silver
alloy or said silver ion.
3. A photo catalytic composite material, comprising: a porous carbon
material; and a photo catalytic material adhered to said porous carbon
material, wherein a value of a specific surface area based on a nitrogen
BET method is equal to or larger than 10 m.sup.2/g, and a volume of a
fine pore based on a BJH method and an MP method is equal to or larger
than 0.1 cm.sup.3/g; and said photo catalytic material is composed of a
titanium oxide doped either with a cation or with an anion.
4. The photo catalytic composite material according to claim 3, wherein
said photo catalytic material absorbs an energy of a light having a
wavelength of 200 to 600 nm.
5. An adsorbent, comprising: a porous carbon material; and an organic
material adhered to said porous carbon material, wherein a value of a
specific surface area based on a nitrogen BET method is equal to or
larger than 10 m.sup.2/g, and a volume of a fine pore based on a BJH
method and an MP method is equal to or larger than 0.1 cm.sup.3/g; and
said organic material adsorbs a metal.
6. The adsorbent according to claim 5, wherein said organic material is
an organic material having at least one kind of group selected from the
group consisting of a phenol group, a carboxyl group, an amino group, a
thiol group, a ketone group, a phosphoric acid group, an alkyl group, an
ether group, and a thionyl group.
7. The adsorbent according to claim 5, wherein said metal is chromium,
mercury, arsenic, lead, cadmium, tin, copper, zinc, lithium, beryllium,
boron, titanium, vanadium, manganese, cobalt, nickel, gallium, germanium,
selenium, rubidium, strontium, zirconium, niobium, molybdenum, palladium,
indium, antimony, tellurium, cesium, barium, hafnium, tantalum, tungsten,
rhenium, platinum, thallium, bismuth, scandium, yttrium, lanthanum,
cerium, praseodymium, neodymium, promethium, samarium, europium,
gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, or
lutetium.
8. A depurative, comprising: a porous carbon material; and an organic
material adhered to said porous carbon material, wherein a value of a
specific surface area based on a nitrogen BET method is equal to or
larger than 10 m.sup.2/g, and a volume of a fine pore based on a BJH
method and an MP method is equal to or larger than 0.1 cm.sup.3/g; and
said organic material adsorbs a metal.
9. The depurative according to claim 8, wherein said organic material is
an organic material having at least one kind of group selected from the
group consisting of a phenol group, a carboxyl group, an amino group, a
thiol group, a ketone group, and a phosphoric acid group.
10. The depurative according to claim 8, wherein said metal is chromium,
mercury, arsenic, lead, cadmium, tin, copper, zinc, lithium, beryllium,
boron, titanium, vanadium, manganese, cobalt, nickel, gallium, germanium,
selenium, rubidium, strontium, zirconium, niobium, molybdenum, palladium,
indium, antimony, tellurium, cesium, barium, hafnium, tantalum, tungsten,
rhenium, platinum, thallium, bismuth, scandium, yttrium, lanthanum,
cerium, praseodymium, neodymium, promethium, samarium, europium,
gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, or
lutetium.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a fungicide which is made of a
porous carbon material complex, a photo catalytic composite material, an
adsorbent, and a depurative.
[0003] 2. Description of the Related Art
[0004] A functional material in which a physical property and a
physicochemical property such as a light absorption property, and an
absorptive capacity for a specific substance are given to a porous
material is an interesting material because the functional material has
both a high specific surface area, and a property of matter which the
functional material has. Here, alumina, carbon, silica or the like can be
given as the porous material. In addition, fine particles or thin films
made of metals such as Fe, Co, Ni, Au, Ag, Pt, or Cu, alloys thereof,
oxides such as Fe.sub.2O.sub.3, Fe.sub.3O.sub.4, TiO.sub.2 or ZnO.sub.2,
compounds such as CdS, CdSe, ZnS, CaCO.sub.3 or Ca(CH.sub.3COO).sub.2, or
the like, or polymeric films or a monomolecular films containing therein
many amino groups can be given as the functional material having the
light absorption property, and the absorptive capacity for the specific
substance.
[0005] For such a functional material, for example, applications to an
absorbent and a catalyst, an electrode for an energy device and a sensing
device are expected. This, for example, is described in Japanese Patent
Laid-Open No. 2006-167694. In addition, although almost unutilized
portions of plants such as a vegetable and a cereal are discarded, the
effective utilization of these unutilized portions is strongly urged for
the maintenance and the improvement of the global environment. A
carbonization treatment is given as an example of the effective
utilization of the unutilized portions of the plants. Also, an example in
which a carbon material manufactured by subjecting such a plant-derived
material to the carbonization treatment is used in a dye absorbent is
known from a non-patent literary document of Dyes and Pigments, Vol. 66,
2005, pp. 123 to 128. In addition, a method of manufacturing a carbide
having a deodorizing ability, an ion exchange capacity, and a catalytic
capacity based on the plant material is well known from Japanese Patent
Laid-Open No. 2000-211910.
[0006] In addition, a fungicide, for example, can be given as a usage of
such a functional material. Components such as fatty acid and glycerin
contained in sweat are decomposed and altered into a lower fatty acid and
the like, thereby generating an armpit odor. Until now, a zeolite
containing therein silver (Ag) has been offered commercially. The zeolite
containing therein Ag is such that Ag ions supported by the zeolite
contacts a normal inhavitant (such as Staphylococcus epidermidis or
diphtheroid fungus) to impede the action of the fungus, thereby cutting
out the source of aroma.
SUMMARY OF THE INVENTION
[0007] The odor eliminating for eliminating the aroma generated, and the
sterilization of the fungus which decompose and alter the components of
the sweat are important in order to prevent the armpit odor from being
generated. However, it is difficult to say that the Ag containing zeolite
described above has the sufficient property in terms of the odor
eliminating and the sterilization. In addition, the functional material,
having the light absorption property, in which a titanium oxide
(TiO.sub.2) is supported by the porous material involves such a problem
that the functional material concerned hardly absorbs a light in a
visible light region and thus does not show the high decomposition
reaction. Or, the porous carbon material as the case may involve such a
problem that the porous carbon material concerned hardly adsorbs the
metal.
[0008] The present invention has been made in order to solve the problems
described above, and it is therefore desirable to provide a fungicide
which is made of a porous carbon material and which has excellent odor
eliminating and sterilization effects, a photo catalytic composite
material which absorbs a light in a visible light region and shows a
decomposition reaction, an adsorbent which adsorbs a metal, and a
depurative.
[0009] In order to attain the desire described above, according to an
embodiment of the present invention, there is provided a fungicide
including: a porous carbon material; and a silver member (silver
material) adhered to the porous carbon material, in which a value of a
specific surface area based on a nitrogen BET, namely Brunauer, Emmett,
and Teller method is equal to or larger than 10 m.sup.2/g, and a volume
of a fine pore based on a BJH, namely Barrett, Joyner, and Halenda method
and an MP, namely Micro Pore method is equal to or larger than 0.1
cm.sup.3/g.
[0010] According to another embodiment of the present invention, there is
provided a photo catalytic composite material including: a porous carbon
material; and a photo catalytic material adhered to the porous carbon
material, in which a value of a specific surface area based on a nitrogen
BET method is equal to or larger than 10 m.sup.2/g, and a volume of a
fine pore based on a BJH method and an MP method is equal to or larger
than 0.1 cm.sup.3/g; and the photo catalytic material is composed of a
titanium oxide doped either with a cation or with an anion.
[0011] According to still another embodiment of the present invention,
there is provided an adsorbent or a depurative including: a porous carbon
material; and an organic material adhered to the porous carbon material,
in which a value of a specific surface area based on a nitrogen BET
method is equal to or larger than 10 m.sup.2/g, and a volume of a fine
pore based on a BJH method and an MP method is equal to or larger than
0.1 cm.sup.3/g; and the organic material adsorbs a metal.
[0012] The fungicide, the photo catalytic composite material, the
adsorbent, and the depurative of the present invention will be
generically hereinafter referred to as "a porous carbon material complex
of the present invention" in some cases. In addition, the silver member,
the photo catalytic material, and the organic material each of which is
to be adhered to the porous carbon material will be generically
hereinafter referred to as "a functional material" in some cases. In
addition, the porous carbon material composing the fungicide, the p
hoto
catalytic composite material, the adsorbent, and the depurative of the
embodiment of the present invention will be hereinafter referred to as
"the porous carbon material in the embodiment of the present invention"
in some cases.
[0013] In each of the fungicide, the photo catalytic composite material,
the adsorbent, and the depurative of the embodiment of the present
invention, the value of the specific surface area based on the nitrogen
BET method is equal to or larger than 10 m.sup.2/g and a volume of a fine
pore based on a BJH method and an MP method is equal to or larger than
0.1 cm.sup.3/g. These requirements can be attained by a porous carbon
material. In addition, the functional material is adhered to such a
porous carbon material, thereby making it possible to increase an amount
of functional material adhered per unit weight of the porous carbon
material. Also, it is possible to obtain the porous carbon material
complex having the high property and the high functionality.
[0014] Also, in the fungicide of the embodiment of the present invention,
the high adsorption property and the high sterilization can be obtained
because the silver member is adhered to the porous carbon material. Thus,
the fungicide can also be utilized as a deodorant product, a deodorizer,
an antimicrobial agent or preserving agent. In addition, in the photo
catalytic composite material of the embodiment of the present invention,
the photo catalytic material is composed of the titanium oxide doped
either with the cation or with the anion. Therefore, the photo catalytic
composite material of the embodiment of the present invention can
effectively absorb the visible light, and thus is given a charge
separation property, a visible light absorption property, an ultraviolet
ray absorption property, and a catalyst property. Thus, the photo
catalytic composite material of the embodiment of the present invention
can be applied as a harmful material decomposition agent, and a harmful
material remover which can be semi-permanently used due to the p
hoto
catalytic effect. In addition, in each of the adsorbent and the
depurative of the embodiment of the present invention, the metal (a metal
atom or a metal ion) can be effectively adsorbed because the organic
material is adhered (supported, adsorbed or bonded) to the porous carbon
material.
[0015] Moreover, the porous carbon material of the embodiment of the
present invention is regulated in its volume of the fine pore, and has a
fine pore in a meso region (in the range of 2 to 50 nm) which cannot be
realized in existing activated carbon in addition to the fine pore in a
micro region (<2 nm) which the existing activated carbon has. Also,
the fungicide of the embodiment of the present invention shows the high
adsorption capacity for the molecules as the cause of the aroma due to
such a fine pore size. In addition thereto, the funguses are adsorbed by
a macro fine pore (>50 nm) having the porous carbon material and
dispersed, thereby also suppressing the growth of the funguses. In
addition, in the photo catalytic composite material of the embodiment of
the present invention, the photo catalytic material can be very
effectively adhered to the porous carbon material based on the fine pore
size as described above, and thus the decomposition based on the photo
catalytic action can be effectively caused. In addition, in each of the
photo catalytic composite material, the adsorbent and the depurative of
the embodiment of the present invention as the material for the
environment depuration, it is expected that the fine pore size as
described above effectively act on the adsorption of the harmful
materials. At the same time, the photo catalytic material or the organic
material can be very effectively adhered to the porous carbon material,
and thus the decomposition and detoxification of the harmful materials
can be effectively caused. In addition, the diffusion of the harmful
materials in the inside of the porous carbon material is promoted, which
results in that the decomposition can be more effectively caused, and the
depuration of the water, and the depuration of the air can be very
effectively carried out.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is electron microscope images of fungicides of Example 1-A
and Example 1-B, and a specimen of Comparative Example 1;
[0017] FIGS. 2A to 2C, and 2D are charts of X-ray diffraction results of
the fungicides of Example 1-A and Example 1-B, and the specimen of
Comparative Example 1 each obtained by using a powder X-ray
diffractometry, and standard data of Ag in an X-ray diffraction analysis,
respectively;
[0018] FIGS. 3A and 3B are graphs representing a fine pore distribution of
meso fine pores, and a fine pore distribution of micro fine pores in the
fungicides of Example 1-A and Example 1-B, and the specimen of
Comparative Example 1, respectively;
[0019] FIG. 4 is a graph representing measurement results of fine pore
diameter distributions about Example 1-A, Example 1-B and Comparative
Example 1 which are obtained by using a non localized density functional
theory method;
[0020] FIG. 5 is a view conceptually showing a state in which a photo
catalytic material absorbs an energy of a light in a photo catalytic
composite material of Example 2;
[0021] FIG. 6 is a graph representing light absorption characteristics of
TiO.sub.2;
[0022] FIG. 7 is a graph representing results of a measurement of a fine
pore (meso fine pore) distribution in specimens of Example 2-A and
Example 2-B;
[0023] FIG. 8 is a graph representing measurement results of fine pore
diameter distributions about Example 2-A and Example 2-B which are
obtained by using the non localized density functional theory method;
[0024] FIG. 9 is a graph representing a state in which each of the photo
catalytic composite material of Example 2-A, and a specimen of
Comparative Example 2 decomposes a tannic acid solution with time;
[0025] FIG. 10 is a graph representing a state in which each of the photo
catalytic composite material of Example 2-B, and a specimen of
Comparative Example 2 decomposes a methyl orange solution with time;
[0026] FIG. 11A is a graph representing results of a decomposition test
about micro cystine based on a specimen of Example 2-B and commercially
available porous carbon, and FIG. 11B is a conceptual view explaining
decomposition of micro cystine in the specimen of Example 2-B;
[0027] FIG. 12 is a view schematically showing a state in which
polyethylene imine as an organic material is adhered to the porous carbon
material in an adsorbent and a depurative of Example 3;
[0028] FIG. 13 is a view schematically showing a state in which the
adsorbent and the depurative of Example 3, an ion exchange capacity can
be enhanced by carrying out a treatment by using FeCl.sub.3.6H.sub.2O;
[0029] FIG. 14 is a graph representing a state in which the adsorbent and
the depurative of Examples 3 and activated carbon of Comparative Example
3 adsorb potassium chromate;
[0030] FIG. 15 is a view schematically showing a state in which the
adsorbent and the depurative of Examples 3 adsorb a chromate ion; and
[0031] FIG. 16 is a graph representing measurement results of fine pore
diameter distributions about Example 3 and Comparative Example 3 which
are obtained by using the non localized density functional theory method.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] Examples of the present invention will be described in detail
hereinafter with reference to the accompanying drawings. However, the
present invention is by no means limited to Examples, and various
numerical values and materials in Examples are merely exemplified. It is
noted that the description will be given below in accordance with the
following order.
[0033] 1. Description about the Whole of Fungicide, Photo Catalytic
Composite Material, Adsorbent, and Depurative of an Embodiment of the
Present Invention
[0034] 2. Example 1 (Fungicide of the Embodiment of the Present Invention)
[0035] 3. Example 2 (Photo Catalytic Composite Material of the Embodiment
of Present Invention)
[0036] 4. Example 3 (Adsorbent and Depurative of the Embodiment of the
Present Invention), and Others
[Description about the Whole of Fungicide, Photo Catalytic Composite
Material, Adsorbent, and Depurative of an Embodiment of the Present
Invention]
[0037] In a fungicide of an embodiment of the present invention, a silver
member (silver material) can be composed of either an ion containing
therein a silver ion; a particle containing therein silver, a silver
alloy or a silver ion; or a thin film containing therein silver, the
silver alloy or the silver ion. Here, an alloy of silver and ruthenium,
an alloy of silver and rhodium, an alloy of silver and palladium, an
alloy of silver and gold, an alloy of silver and platinum, an alloy of
silver and cobalt, an alloy of silver and nickel, or an alloy of silver
and copper can be exemplified as the silver alloy. Also, a form of silver
nitrate, a form of silver chloride, or a form of silver sulfate can be
exemplified as the silver ion. A method such as impregnation in a silver
salt aqueous solution, or reduction and precipitation of silver by using
a reducing agent can be exemplified as a method of adhering the silver
member to a porous carbon material.
[0038] In addition, in a photo catalytic composite material of the
embodiment of the present invention, a photo catalytic material can have
a constitution that an energy of a light having a wavelength of 200 to
600 nm is absorbed. The photo catalytic material is composed of a
titanium oxide doped either with a cation (positive ion) or with an anion
(negative ion). Here, a chromium ion, an iron ion, a silver ion, a
platinum ion, a copper ion, a tungsten ion, or, a cobalt ion or a nickel
ion can be exemplified as a concrete example of the cation. Also, a
nitrogen ion, a carbon ion, or a sulfur ion can be exemplified as a
concrete example of the anion. A method in which crystal growth is
carried out in a state in which a substance containing therein either a
cation or an anion, and a raw material of a titanium oxide are mixed with
each other, a method in which crystal growth is carried out from a
substance in the form of gas containing therein either a cation or an
anion, and a raw material of a titanium oxide in the form of gas, or a
method in which after completion of synthesis of a titanium oxide, either
a cation or an anion is supported on a surface of the titanium oxide can
be exemplified as a method of doping the titanium oxide with either the
cation or the anion. Adhesion in a state of a fine particle, or adhesion
in a state of a thin film can be exemplified as a form of the adhesion of
the titanium oxide to the porous carbon material. It is noted that a zinc
oxide (ZnO) can also be used instead of using the titanium oxide.
[0039] A depurative can be obtained from the photo catalytic composite
material of the embodiment of the present invention. For decomposition
and removal of harmful substances, a visible light has to be radiated to
the p
hoto catalytic composite material of the embodiment of the present
invention. Harmful substances each existing either in water or in air can
be given as the harmful substances. Specifically, it is possible to
exemplify a micro-cystine class or substances as sources of various kinds
of virus or allergy. The depurative functions either as a depurative for
water, or as a depurative for air, and thus, for example, can be applied
as a filter of an air purification apparatus. Use in a sheet-like form,
use in a state of being filled either in a column or in a cartridge, use
in a state of being formed into a desired shape by using a binder or the
like, or use in a powder form can be exemplified as a use form of the
photo catalytic composite material (depurative) of the embodiment of the
present invention. In addition, when the photo catalytic composite
material is used as a depurative or an adsorbent dispersed in a solution,
the photo catalytic composite material can be used by subjecting a
surface thereof either to a hydrocolloid treatment or to a hydrophobic
treatment.
[0040] In the adsorbent or the depurative of the embodiment of the present
invention, an organic material having at least one kind of group selected
from the group consisting of a phenol group, a carboxyl group, an amino
group, a thiol group, a ketone group, a phosphoric acid group, an alkyl
group, an ether group, and a thionyl group can be given as the organic
material. Specifically, for example, polyethyleneimine can be given as
the organic material. In addition, chromium, mercury, arsenic, lead,
cadmium, tin, copper, zinc, lithium, beryllium, boron, titanium,
vanadium, manganese, cobalt, nickel, gallium, germanium, selenium,
rubidium, strontium, zirconium, niobium, molybdenum, palladium, indium,
antimony, tellurium, cesium, barium, hafnium, tantalum, tungsten,
rhenium, platinum, thallium, bismuth, scandium, yttrium, lanthanum,
cerium, praseodymium, neodymium, promethium, samarium, europium,
gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, or
lutetium can be given as the metal (including a metal atom and a metal
ion). A method of forming C--C bond, C--N bond, CO bond or the like
between the porous carbon material and the organic molecule, a method of
coating SiO.sub.2 and bonding the organic material to the porous carbon
material by silane coupling, or a mixing and stirring method, for
example, can be exemplified as the method of adhering (including the
concept such as support, adsorption, bonding and surface modification)
the organic material to the porous carbon material. The adhesion in a
layer-like form, or the adhesion in an island-like form can be
exemplified as a form of the adhesion of the organic material to the
porous carbon material. It is noted that each of the adsorbent and the
depurative of the embodiment of the present invention, for example, can
enhance the negative ion exchange capacity or the positive ion exchange
capacity, or can adsorb the metals (such as the metal atom and the metal
ion) having various kinds of forms by changing a metal coordination or
the like. In addition, each of the adsorbent and the depurative of the
embodiment of the present invention can enhance the dispersibility either
to a solvent or to the base.
[0041] Here, each of the adsorbent and the depurative of the embodiment of
the present invention, for example, functions as a depurative for water
and, for example, can also be applied to a filter. Also, the use in the
sheet-like form, the use in the state of being filled either in the
column or in the cartridge, the use in the state of being formed into the
desired shape by using the binder or the like, or the use in the powder
form can be exemplified as the use form. In addition, each of the
adsorbent and the depurative the embodiment of the present invention can
also absorb the metal contained in the gas such as smoke.
[0042] When the plant-derived material containing therein silicon (Si) is
used as the raw material of the porous carbon material in the present
invention, specifically, although a limitation is by no means carried
out, preferably, the porous carbon material has the plant-derived
material in which a content rate of silicon (Si) is equal to or larger
than 5 wt % as the raw material. In this case, the content rate of
silicon (Si) is equal to or smaller than 5 wt %, preferably is equal to
or smaller than 3 wt %, and more preferably is equal to or smaller than 1
wt %.
[0043] For example, after the plant-derived material is carbonized at 400
to 1,400.degree. C., the resulting material is treated by using either an
acid or an alkali, thereby obtaining the porous carbon material. After
that, the functional material is adhered to the resulting porous
material, thereby making it possible to manufacture the porous carbon
material complex of the embodiment of the present invention. In a method
of manufacturing such a porous carbon material in the embodiment of the
present invention (hereinafter simply referred to as "a method of
manufacturing the porous carbon material" in some cases), a material
which is obtained by carbonizing the plant-derived material at 400 to
1,400.degree. C. before being treated by either using an acid or using an
alkali is referred to either as "a porous carbon material precursor" or
as "a carbonaceous material."
[0044] In the method of manufacturing the porous carbon material, after
completion of the treatment either using the acid or using the alkali, a
process for carrying out an activation treatment before the functional
material is adhered to the porous carbon material can be contained, or
the treatment either using the acid or using the alkali may be carried
out after the activation treatment is carried out for the porous carbon
material. In addition, in the method of manufacturing the porous carbon
material including such a preferable form, although depending on the
plant-derived material used, before the plant-derived material is
carbonized, the plant-derived material may be subjected to the heat
treatment (preliminary carbonizing treatment) at the lower temperature
(for example, in the range of 400 to 700.degree. C.) than that for the
carbonization in a state in which oxygen is cut off. As a result, a tar
component which will be generated in a process of carbonization can be
extracted. As a result, the tar component which will be generated in the
process of the carbonization can be either reduced or removed away. It is
noted that, for example, an atmosphere of inactive gas such as a nitrogen
gas or argon gas is prepared, or a vacuum atmosphere is prepared, or the
plant-derived material is set in a sort of escalloped state, thereby
making it possible to attain the state in which oxygen is cut off. In
addition, in the method of manufacturing the porous carbon material,
although depending on the plant-derived material used, for the purpose of
reducing a mineral component and water contained in the plant-derived
material, and for the purpose of preventing off-flavor from being
generated in the process for the carbonization, the plant-derived
material may be dipped in alcohol (such as methyl alcohol, ethyl alcohol
or isopropyl alcohol). It is noted that in the method of manufacturing
the porous carbon material, after that, the preliminary carbonizing
treatment may be carried out. A plant which generates a large amount of
wood vinegar (such as tar or light oil content), for example, can be
given as the material which is preferably subjected to the heat treatment
in the inactive gas. In addition, a seaweed which contains therein a
large amount of iodine or various minerals, for example, can be given as
the material which is preferably subjected to the pretreatment using the
alcohol.
[0045] In the method of manufacturing the porous carbon material, the
plant-derived material is carbonized at 400 to 1,400.degree. C. Here, the
carbonization generally means that the organic material (the porous
carbon material in the embodiment of the present invention) is subjected
to the heat treatment to be transformed into the carbonaceous material
(for example, refer to JIS M0104-1984). It is noted that an atmosphere in
which oxygen is cut off can be given as the atmosphere for the
carbonization. Specifically, it is possible to give the vacuum
atmosphere, the atmosphere of the inactive gas such as nitrogen gas or
argon gas, or the atmosphere in which the plant-derived material is made
to undergo the sort of escalloped state. Although not limited especially,
1.degree. C./minute or more, preferably, 3.degree. C./minute or more, or
more preferably, 5.degree. C./minute or more can be given as a rate of
temperature rise in such an atmosphere until the carbonization
temperature is reached. In addition, although 10 hours, preferably 7
hours, and more preferably 5 hours can be given as an upper limit of the
carbonization time, the present invention is by no means limited thereto.
Also, a lower limit of the carbonization time has to be set as a time for
which the plant-derived material is reliably carbonized. In addition, the
plant-derived material may be crushed to pieces each having a desired
particle size as may be necessary, or may be classified. The
plant-derived material may be previously cleaned. Or, the resulting
porous carbon material precursor or porous carbon material may be crushed
to pieces each having a desired particle size as may be necessary, or may
be classified. Or, the porous carbon material after completion of the
activation treatment may be crushed to pieces each having a desired
particle size as may be necessary, or may be classified. In addition, a
sterilization treatment may be carried out for the porous carbon material
which is finally obtained. There is no limit to a type, a constitution
and a construction of a furnace which is used for the carbonization. That
is to say, a continuous furnace can be used, or a batch furnace can also
be used.
[0046] In the method of manufacturing the porous carbon material, as
previously stated, when the plant-derived material is subjected to the
activation treatment, it is possible to increase the number of micro-fine
pores (which will be described later) each having a pore diameter smaller
than 2 nm. A gas activation method or a drug activation method can be
given as a method for the activation treatment. Here, the gas activation
method means a method in which oxygen, steam, carbon dioxide gas, air or
the like is used as an activator, and the porous carbon material is
heated at 700 to 1,400.degree. C., preferably at 700 to 1,000.degree. C.,
and more preferably at 800 to 1,000.degree. C. for several tens of
minutes to several hours, whereby a fine structure is developed by
volatile components and carbon molecules in the porous carbon material.
It is noted that more specifically, the heating temperature may be
suitably selected in accordance with a kind of plant-derived material, a
kind of gas, a concentration of gas, and the like. The drug activation
method means a method in which the plant-derived material is activated by
using zinc chloride, iron chloride, calcium phosphate, calcium hydroxide,
magnesium carbonate, kalium carbonate, a sulfuric acid, or the like
instead of using oxygen or steam used in the gas activation method, is
rinsed by using a hydrochloric acid, is adjusted in pH by using an
alkaline aqueous solution, and is then dried.
[0047] In the method of manufacturing the porous carbon material, the
silicon components in the plant-derived material after completion of the
carbonization are removed away by carrying out the treatment using either
the acid or the alkali. Here, silicon oxides such as a silicon dioxide,
oxidized silicon, and a silicon oxide salt can be given as the silicon
components. The silicon components in the plant-derived material after
completion of the carbonization are removed away in the manner as
described above, whereby it is possible to obtain the porous carbon
material having a high specific surface area, and it is also possible to
increase an amount of functional material adhered per unit weight of the
porous carbon material. The silicon components contained in the
plant-derived material after completion of the carbonization may be
removed away based on a dry etching method as the case may be.
[0048] That is to say, in the preferable form of the porous carbon
material in the embodiment of the present invention, the plant-derived
material containing therein silicon (Si) is used as the raw material.
However, when the plant-derived material is transformed either into a
porous carbon material precursor or into a carbonaceous material, the
plant-derived material is carbonized at a high temperature (for example,
in the range of 400 to 1,400.degree. C.), whereby silicon contained in
the plant-derived material does not turn into a silicon carbide (SiC),
but exists as silicon components (silicon oxides) such as a silicon
dioxide (SiO.sub.x), a silicon oxide and a silicon oxide salt. For this
reason, a treatment is carried out in a next process by either using an
acid or using an alkali (base), thereby removing away the silicon
components (silicon oxides) such as the silicon dioxide, the silicon
oxide and the silicon oxide salt. As a result, it is possible to obtain a
value of a large specific surface area based on a nitrogen BET method.
[0049] In addition, in the preferable form of the porous carbon material
in the embodiment of the present invention, the porous carbon material in
the embodiment of the present invention is a natural product-derived
environment conciliatory material. A fine structure of the porous carbon
material is obtained by treating the silicon components (silicon oxides)
previously contained in the raw material as the plant-derived material by
either using the acid or using the alkali to remove away the silicon
components. Therefore, an arrangement of the fine pores maintains the
biological body regularity which the plant has.
[0050] As described above, in the porous carbon material, the
plant-derived material can be used as the raw material. Here, a rice hull
or a straw of rice (rice plant), barley, wheat, rye, a barnyard grass,
millet or the like, a coffee bean, a tea leave (such as a leave of a
green tea or a red tea), a sugar cane class (more specifically, a cone
trash of the sugar cane class), a corn class (more specifically, a core
of the corn class), or a coat of a fruit (such as a coat of an orange or
a banana), or a reed or a stalk brown seaweed can be given as the
plant-derived material. However, the present invention is by no means
limited thereto. Or, for example, it is possible to give a vascular
plant, a pteridophyte, or a bryophyte which is vegetated on the land, an
alga or a sea alga. It is noted that these materials also may be used
either in the form of singularity or in the form of multiple kinds of
materials mixed with one another as the raw material. In addition, a
shape and a form of the plant-derived material are especially by no means
limited. For example, the rice hull or straw itself may be used, or a
product obtained by subjecting the plant-derived material to a drying
treatment may also be used. In addition, it is possible to use a product
which is subjected to various kinds of treatments such as a formentation
treatment, a roasting treatment and an extraction treatment in processing
for food and drink such as beer, and wines and spirits. In particular, it
is preferable to use the straw and the rice hull after completion of the
processing such as the thrashing from a viewpoint of the recycling of the
industrial waste. These straw and rice hull after completion of the
processing, for example, are available in large numbers and readily from
an agricultural cooperative, an alcoholic drinks manufacturing company, a
food company, or a food-processing company.
[0051] In the porous carbon material complex of the embodiment of the
present invention, although depending on the kind, constitution,
structure and form of the functional material, as described above, a
state in which the functional material is adhered as the ions, a state in
which the functional material is adhered as the fine particle to the
surface (including the inside of the fine pore) of the porous carbon
material, a state in which the functional material is adhered as the fine
particle to the surface (including the inside of the fine pore) of the
porous carbon material, a state in which the functional material is
adhered in the thin film form, a state in which the functional material
is adhered in the sea/island form (when the surface of the porous carbon
material is regarded as "the sea," the functional material corresponds to
"the island") can be given as the form of the adhesion of the functional
material to the porous carbon material. It is noted that the adhesion
means the phenomenon of the adhesion between different kinds of
materials. Although depending on the functional material, a method in
which the porous carbon material is dipped in the solution containing
therein the functional material or a precursor thereof, thereby
precipitating the functional material on the surface of the porous carbon
material, a method in which the functional material is precipitated on
the surface of the porous carbon material by using a nonelectrolytic
plating method (chemical plating method) or a chemical reduction
reaction, or a method in which the porous carbon material is dipped in
the solution containing therein the precursor of the functional material,
and the heat treatment is carried out, thereby precipitating the
functional material on the surface of the porous carbon material can be
given as the general method of adhering the functional material to the
porous carbon material. Or, a method in which the porous carbon material
is dipped in the solution containing therein the precursor of the
functional material, and an ultrasonic radiation treatment is carried
out, thereby precipitating the functional material on the surface of the
porous carbon material, or a method in which the porous carbon material
is dipped in the solution containing therein the precursor of the
functional material, and a sol/gel reaction is carried out, thereby
precipitating the functional material on the surface of the porous carbon
material can be given as the general method of adhering the functional
material to the porous carbon material.
[0052] A nonmetal element such as magnesium (Mg), kalium (K), calcium
(Ca), phosphorus (P) or sulfur (S), or a metal element such as a
transition element may be contained in the porous carbon material in the
embodiment of the present invention. As the content rate of magnesium
(Mg), 0.01 wt % or more and 3 wt % or less can be given, 0.01 wt % or
more and 3 wt % or less can be given as the content rate of kalium (K),
0.05 wt % or more and 3 wt % or less can be given as the content rate of
calcium (Ca), 0.01 wt % or more and 3 wt % or less can be given as the
content rate of phosphorus (P), and 0.01 wt % or more and 3 wt % or less
can be given as the content rate of sulfur (S). It is noted that although
the content rates of these elements differ depending on the use
application of the porous carbon material complex of the embodiment of
the present invention, preferably, the content rates of these elements
are each less from a viewpoint of an increase in value of the specific
surface area. It goes without saying that the porous carbon material may
contain any of elements other than the elements described above, and the
ranges of the content rates of the various kinds of elements described
above can change depending on the use application of the porous carbon
material complex of the embodiment of the present invention.
[0053] In the present invention, the analyses about the various kinds of
elements can be carried out in accordance with an energy dispersion
method (EDS) by using an energy dispersive X-ray analyzer (such as
JED-2200F made by JAPAN ELECTRON OPTICS LABORATORY CO., LTD.). Here, a
measurement condition, for example, has to be set in such a way that a
scanning voltage is 15 kV, and a radiation current is 10 .mu.A.
[0054] The porous carbon material complex of the embodiment of the present
invention has many fine pores. "A meso fine pore" having a pore diameter
of 2 to 50 nm, and "a micro fine pore" having a pore diameter smaller
than 2 nm are contained as the fine pore in the porous carbon material
complex. Specifically, the porous carbon material complex, for example,
contains therein many fine pores each having the pore diameter of 20 nm
or less as the meso fine pores, especially, contains therein many fine
pores each having the pore diameter of 10 nm or less. In addition, the
porous carbon material complex, for example, contains therein many fine
pores each having the pore diameter of about 1.9 nm, many fine pores each
having the pore diameter of about 1.5 nm, and many fine pores each having
the pore diameter of 0.8 to 1 nm as the micro fine pores. Although in the
porous carbon material complex of the present invention, a volume of the
fine pore based on both the BJH method and the MP method is equal to or
larger than 0.1 cm.sup.3/g, more preferably, equal to or larger than 0.3
cm.sup.3/g. Or, the volume of the fine pore based on the BJH method is
preferably equal to or larger than 0.1 cm.sup.3/g, more preferably is
equal to or larger than 0.3 cm.sup.3/g, and much more preferably is equal
to or larger than 0.5 cm.sup.3/g.
[0055] In the porous carbon material complex of the embodiment of the
present invention, for the purpose of obtaining the more excellent
functionality, it is desirable that the value of the specific surface
area based on the nitrogen BET method (hereinafter referred simply to as
"the value of the specific surface area" in some cases) is preferably
equal to or larger than 50 m.sup.2/g, is more preferably equal to or
larger than 100 m.sup.2/g, and is much more preferably equal to or larger
than 400 m.sup.2/g.
[0056] The nitrogen BET method means a method in which an adsorption
isotherm is measured by adsorbing and desorbing nitrogen molecules as
adsorbed molecules to and from the adsorbent (the porous carbon material
complex in this case), and data obtained through the measurement is
analyzed based on a BET expression expressed by Expression (1). Thus, the
specific surface area, the fine pore volume and the like can be
calculated based on the nitrogen BET method. Specifically, when the value
of the specific surface area is calculated by using the nitrogen BET
method, firstly, the adsorption isotherm is obtained by adsorbing and
desorbing the nitrogen molecules as adsorbed molecules to and from the
adsorbent (porous carbon material complex). Also,
[p/{V.sub.a(p.sub.0-p)}] is calculated from the resulting adsorption
isotherm based either on Expression (1) or on Expression (1') into which
Expression (1) is transformed, and data on [p/{V.sub.a(p.sub.0-p)}] is
then plotted against an equilibrium relative pressure (p/p.sub.0). Also,
the line obtained based on the data plotting is regarded as a straight
line, and a slop s (=[(C-1)/(CV.sub.m)] and an intercept i
(=[1/(CV.sub.m)] are calculated based on a least-squares method. Also,
V.sub.m and C are calculated from the slope, s, and intercept, i, thus
obtained based on Expression (2-1) and Expression (2-2). In addition, a
specific surface area, a.sub.sBET, is calculated from V.sub.m based on
Expression (3). This calculation, for example, is described in a manual
of BELSORP-mini and BELSORP analysis software made by BEL JAPAN, INC.,
pp. 62 to 66. It should be noted that the nitrogen BET method is a
measurement method conforming to JIS R 1626-1996 "A method of measuring a
specific surface area based on a gas adsorption BET method for fine
ceramics powder."
V.sub.a=(V.sub.mCp)/[(p.sub.0-p){1+(C-1)(p/p.sub.0)}] (1)
[p/{V.sub.a(p.sub.0-p)}]=[(C-1)/(CV.sub.m)](p/p.sub.0)+[1/(CV.sub.m)]
(1')
V.sub.m=1/(s+i) (2-1)
C=(s/i)+1 (2-2)
a.sub.sBET=(V.sub.mL.sigma.)/22414 (3)
[0057] where V.sub.a is an amount of adsorption, V.sub.m is an amount of
adsorption of a single molecule layer, p is a pressure in a phase of
equilibrium of nitrogen, p.sub.0 is a saturated vapor pressure, L is an
Avogadro's number, and .sigma. is an adsorption cross section of
nitrogen.
[0058] When the fine pore volume, V.sub.p, is calculated based on the
nitrogen BET method, for example, the adsorption data on the adsorption
isotherm thus obtained is linearly interpolated, thereby obtaining the
amount, V, of adsorption at the relative pressure set in the fine pore
volume calculation relative pressure. The fine pore volume V.sub.p can be
calculated from the amount, V, of adsorption based on Expression (4).
This calculation, for example, is described in the manual of BELSORP-mini
and BELSORP analysis software made by BEL JAPAN, INC., pp. 62 to 66. It
is noted that the fine pore volume based on the nitrogen BET method will
be referred hereinafter simply to as "a fine pore volume" in some cases.
V.sub.p=(V/22414).times.(M.sub.g/.rho..sub.g) (4)
[0059] where V is an amount of adsorption at the relative pressure,
M.sub.g is molecular weight of nitrogen, and .rho..sub.g is a density of
nitrogen.
[0060] The pore diameter of the meso fine pore, for example, can be
calculated in the form of a distribution of the fine pores from a change
ratio of the fine pore volume to the pore diameter based on the BJH
method. The BJH method is a method which is widely used as a fine pore
distribution analyzing method. When the fine pore distribution analysis
is carried out based on the BJH method, firstly, the adsorption isotherm
is obtained by adsorbing and desorbing the nitrogen molecules as adsorbed
molecules to and from the adsorbent (porous carbon material complex).
Also, a thickness of the adsorption layer when the adsorbed molecules are
adsorbed and desorbed step by step from a state in which the fine pores
are filled with the adsorbed molecules (for example, the nitrogen
molecules), and an inner diameter of each of the pores (which is double
the core radius) which are generated in this case are obtained based on
the resulting adsorption isotherm, a fine pore radius, r.sub.p, is
calculated based on Expression (5), and a fine pore volume is calculated
based on Expression (6). Also, the change ratio (dV.sub.p/dr.sub.p) of
the fine pore volume to the fine pore diameter, 2r.sub.p, is plotted from
both the fine pore radius and the fine pore volume, thereby obtaining a
fine pore distribution curve. This calculation, for example, is described
in the manual of BELSORP-mini and BELSORP analysis software made by BEL
JAPAN, INC., pp. 85 to 88.
r.sub.P=t+r.sub.k (5)
V.sub.pn=R.sub.ndV-R.sub.ndtc.SIGMA.A.sub.pj (6)
R.sub.n=r.sub.pn.sup.2/(r.sub.kn-1+dt.sub.n).sup.2 (7)
[0061] where r.sub.p is the fine pore radius, and r.sub.k is the inner
radius of the core (inner diameter/2) when the adsorption layer having a
thickness, t, is adsorbed to an inner wall of the fine pore having the
fine pore radius, r.sub.p, at the pressure set therein, V.sub.p, is the
fine pore volume when the n-th round of adsorption and desorption of the
nitrogen molecules are generated, and dV.sub.n is a change rate at this
time. Further, dt.sub.n is a change rate of the thickness, t.sub.n, of
the adsorption layer when the n-th round of adsorption and desorption of
the nitrogen molecules are generated, r.sub.kn is a core radius at this
time, c is a fixed value, r.sub.pn is the fine pore radius when the n-th
round of adsorption and desorption of the nitrogen molecules is
generated, and .SIGMA.A.sub.pj represents an integrated value of an area
of a wall surface of the fine pore from j=1 to j=n-1.
[0062] The pore diameter of the micro fine pore, for example, can be
calculated in the form of a distribution of the fine pores from the
change ratio of the fine pore volume to the pore diameter based on the MP
method. When the fine pore distribution analysis is carried out based on
the MP method, firstly, the adsorption isotherm is obtained by adsorbing
the nitrogen molecules to the adsorbent (porous carbon material complex).
Also, the adsorption isotherm is transformed into the fine pore volume
relative to the thickness, t, of the adsorption layer (is t-plotted).
Also, the fine pore distribution curve can be obtained based on a
curvature (an amount of change in fine pore volume relative to an amount
of change in thickness, t, of the adsorption layer). This calculation,
for example, is described in the manual of BELSORP-mini and BELSORP
analysis software made by BEL JAPAN, INC., pp. 72 and 73, and p. 82.
[0063] In the Non Localized Density Functional Theory method (NLDFT
method) regulated in JIS Z8831-2: 2010 "A fine pore distribution and fine
pore characteristics of powder (solid)--the second part: A method of
measuring a meso fine pore and a macro fine pore based on gas
adsorption," and JIS Z8831-3: 2010 "A fine pore diameter distribution and
fine pore characteristics of powder (solid)--the third part: A method of
measuring a micro fine pore based on gas adsorption," software that comes
with an automatic specific surface area/fine pore distribution measuring
apparatus "BELSORP-MAX" manufactured by BEL JAPAN, INC. is used as
analysis software. A model is formed so as to have a cylindrical shape
and carbon black (CB) is assumed as the prerequisite, and a distribution
function of a fine pore distribution parameter is set as "no-assumption."
The smoothing is carried out ten times for the resulting distribution
data.
[0064] Here, when the fungicide of the embodiment of the present invention
is regulated based on the non localized density functional theory method,
the fungicide of the embodiment of the present invention for attaining
the desire described above includes:
[0065] (A) a porous carbon material; and
[0066] (B) a silver member (silver material) adhered to the porous carbon
material.
[0067] In addition, when the photo catalytic composite material of the
embodiment of the present invention is regulated based on the non
localized density functional theory method, the photo catalytic composite
material of the embodiment of the present invention for attaining the
desire described above includes:
[0068] (A) a porous carbon material; and
[0069] (B) a photo catalytic material adhered to the porous carbon
material, and
[0070] the p
hoto catalytic material is composed of a titanium oxide doped
either with a cation or with an anion.
[0071] When the adsorbent or the depurative of the embodiment of the
present invention is regulated based on the non localized density
functional theory method, the adsorbent or the depurative of the
embodiment of the present invention for attaining the desire described
above includes:
[0072] (A) a porous carbon material; and
[0073] (B) an organic material adhered to the porous carbon material, and
[0074] the organic material adsorbs a metal.
[0075] Also, in the fungicide of the embodiment of the present invention,
the photo catalytic composite material of the embodiment of the present
invention, and the adsorbent or the depurative of the embodiment of the
present invention, the value of the specific surface area based on the
nitrogen BET method is equal to or larger than 10 m.sup.2/g, and the
total of the volumes of the fine pores having the diameters in the range
of 1.times.10.sup.-9 to 5.times.10.sup.-7 m obtained based on the non
localized density functional theory method is equal to or larger than 0.1
cm.sup.3/g. Or, the value of the specific surface area based on the
nitrogen BET method is equal to or larger than 10 m.sup.2/g, and a rate
of the total of the volumes of the fine pores having at least one peak in
the range of 3 to 20 nm, and having the fine pore diameters in the range
of 3 to 20 nm in the fine pore diameter distribution obtained based on
the non localized density functional theory method is equal to or larger
than 0.2 of the total of the volumes of all the fine pores.
[0076] The porous carbon material precursor is treated by using either the
acid or the alkali. In this case, a method of dipping the porous carbon
material precursor in an aqueous solution of either the acid or the
alkali, or a method of causing the porous carbon material precursor and
the acid or the alkali to react with each other in a gas phase, for
example, can be given as the concrete treatment method. More
specifically, when the porous carbon material precursor is treated by
using the acid, a fluorine compound, showing an acidic property, such as
hydrogen fluoride, a hydrofluoric acid, ammonium fluoride, calcium
fluoride or sodium fluoride can be given as the acid. When the fluorine
compound is used, fluorine elements have to be four times in its amount
as large as the silicon elements in the silicon components contained in
the porous carbon material precursor. Thus, preferably, the concentration
of the fluorine compound aqueous solution is equal to or larger than 10
wt %. When the silicon components (such as the silicon dioxide) contained
in the porous carbon material precursor are removed away by using the
hydrofluoric acid, the silicon dioxide reacts with the hydrofluoric acid
as shown either in Chemical Formula (A) or in Chemical Formula (B) to be
removed away either as a hexafluorosilicic acid (H.sub.2SiF.sub.6) or as
silicon tetrafluoride (SiF.sub.4), thereby making it possible to obtain
the porous carbon material. Also, after that, the rinsing and the drying
have to be carried out.
SiO.sub.2+6HF.fwdarw.H.sub.2SiF.sub.6+2H.sub.2O (A)
SiO.sub.2+4HF.fwdarw.SiF.sub.4+2H.sub.2O (B)
[0077] On the other hand, when the porous carbon material precursor is
treated by using the alkali (base), sodium hydroxide, for example, can be
given as the alkali. When an aqueous solution of the alkali, pH of the
aqueous solution has to be equal to or larger than 11. When the silicon
compounds (for example, the silicon dioxide) contained in the porous
carbon material precursor are removed away by using the sodium hydroxide
aqueous solution, the silicon dioxide reacts with the sodium hydroxide as
shown in Chemical Formula (C) by heating sodium hydroxide aqueous
solution to be removed away as sodium silicate (Na.sub.2SiO.sub.3),
thereby making it possible to obtain the porous carbon material. Also,
when the porous carbon material precursor is treated to react with sodium
hydroxide aqueous solution in a gas phase, the silicon dioxide reacts
with the sodium hydroxide as shown in Chemical Formula (C) by heating a
solid substance of sodium hydroxide to be removed away as sodium silicate
(Na.sub.2SiO.sub.3), thereby making it possible to obtain the porous
carbon material. Also, after that, the rinsing and the drying have to be
carried out.
SiO.sub.2+2NaOH.fwdarw.Na.sub.2SiO.sub.3+H.sub.2O (C)
[0078] Or, the porous carbon material, for example, disclosed in Japanese
Patent Laid-Open No. 2010-106007 and including vacancies having
three-dimensional regularity (the porous carbon material having a
so-called inverted-opal structure) can also be used as the porous carbon
material in the embodiment of the present invention. Specifically, the
porous carbon material which includes the spherical vacancies having an
average diameter of 1.times.10.sup.-9 to 1.times.10.sup.-5 m, and
three-dimensionally disposed, and which has the specific surface area
equal to or larger than 3.times.10.sup.2 m.sup.2/g, preferably, the
porous carbon material in which macroscopically, the vacancies are
arranged in a disposition state corresponding to a crystal structure, or
macroscopically, the vacancies are arranged on the surface of the porous
carbon material in a disposition state corresponding to (111) surface
orientation in a face-centered cubic structure can also be used as the
porous carbon material in the embodiment of the present invention.
Example 1
[0079] Example 1 relates to the fungicide of the embodiment of the present
invention. The fungicide of Example 1 includes:
[0080] (A) a porous carbon material specifically, having a plant-derived
material containing therein silicon as a raw material, more specifically,
a porous carbon material having a plant-derived material containing
therein silicon having a content rate of 5 wt % or more as a raw
material, the content rate of silicon being equal to or smaller than 1 wt
%; and
[0081] (B) a silver member (silver material) adhered to the porous carbon
material,
[0082] in this case, a value of a specific surface area based on the
nitrogen BET method is equal to or larger than 10 m.sup.2/g, and a volume
of a fine pore based on both the BJH method and the MP method is equal to
or larger than 0.1 cm.sup.3/g.
[0083] Or, the fungicide of Example 1 includes:
[0084] (A) a porous carbon material; and
[0085] (B) a silver member (silver material) adhered to the porous carbon
material, and
[0086] the value of the specific surface area based on the nitrogen BET
method is equal to or larger than 10 m.sup.2/g, and the total of the
volumes of the fine pores having the diameters in the range of
1.times.10.sup.-9 to 5.times.10.sup.-7 m obtained based on the non
localized density functional theory method is equal to or larger than 0.1
cm.sup.3/g. Or, the value of the specific surface area based on the
nitrogen BET method is equal to or larger than 10 m.sup.2/g, and a rate
of the total of the volumes of the fine pores having at least one peak in
the range of 3 to 20 nm, and having the fine pore diameters in the range
of 3 to 20 nm in the fine pore diameter distribution obtained based on
the non localized density functional theory method is equal to or larger
than 0.2 of the total of the volumes of all the fine pores.
[0087] In Example 1, a rice hull of rice (rice plant) was used as the
plant-derived material as the raw material of the porous carbon material.
Also, the rice hull as the raw material is carbonized to be transformed
into a carbonaceous material (the porous carbon material precursor), and
the resulting carbonaceous material is then subjected to an acid
treatment, thereby obtaining the porous carbon material in Example 1.
Also, after the porous carbon material is obtained in the manner as
described above, a functional material (silver member) is adhered
(supported, adsorbed or bonded) to the porous carbon material, thereby
making it possible to obtain a porous carbon material complex
(fungicide). Specifically, in Example 1, the silver member is composed of
silver (silver of a metal), and is adhered in the form of a form and a
shape of a fine particle to a surface (including an inside of the fine
pore) of the porous carbon material. Hereinafter, a method of
manufacturing the fungicide of Example 1 will be described.
[Process 100-A]
[0088] In the manufacture of the fungicide of Example 1, firstly, after
the plant-derived material was carbonized at 400 to 1,400.degree. C., the
resulting material is treated by using either the acid or the alkali,
thereby obtaining the porous carbon material. That is to say, firstly,
the rice hull was subjected to the heating treatment (preliminary
carbonizing treatment) in the inactive gas. Specifically, the rice hull
was heated at 500.degree. C. for 5 hours in the nitrogen gas-flow to be
carbonized, thereby obtaining a carbide. It is noted that by carrying out
such a treatment, the tar component which will be generated during the
next carbonization can be either reduced or removed away. After that, 10
g of the carbide was put in a crucible made of alumina, and a temperature
of 10 g of the carbide was made to rise to 800.degree. C. at a rate of
temperature rise of 5.degree. C./minute in the nitrogen gas flow (5
l/minute). Also, after the carbide was carbonized at 800.degree. C. for 1
hour to be transformed into the carbonaceous material (porous carbon
material precursor), the resulting porous carbon material precursor was
cooled to a room temperature. It is noted that during the carbonization
and the cooling, the nitrogen gas was continuously flowed. Next, after
the porous carbon material precursor was dipped in 46 vol % hydrofluoric
acid aqueous solution through the night, thereby carrying out the acid
treatment, the carbonaceous material was rinsed until pH 7 was obtained
by using water and ethyl alcohol. It is noted that the porous carbon
material thus obtained is referred to as "a porous carbon material-A" for
the sake of convenience. Next, after the porous carbon material thus
obtained was dried at 120.degree. C., the porous carbon material was
heated at 900.degree. C. for 3 hours in a steam gas-flow to carry out an
activation treatment, thereby making it possible to obtain the desired
porous carbon material. It is noted that the porous carbon material thus
obtained is referred to as "a porous carbon material-B" for the sake of
convenience.
[Process-110A]
[0089] Next, a silver material was adhered (supported, adsorbed or bonded)
to the resulting porous carbon material-B. It is noted that the treatment
for adhering the functional material to the porous carbon material will
be hereinafter referred to as "a compound treatment" in some cases.
Specifically, 0.43 g of the porous carbon material-B was added to 182 ml
of distilled water, and the stirring was carried out for 30 minutes.
Also, after 8 ml of 5 mmol/l of a silver nitrate aqueous solution was
added thereto, and the stirring was further carried out for 1 hour, 10 ml
of 40 mmol/l of sodium boron hydride was added thereto, and the stirring
was carried out through the night. After the resulting powder was
filtered by using a filter and was then rinsed by using distilled water,
the drying was carried out at 120.degree. C., thereby obtaining the
fungicide of Example 1-A.
[Process-110B]
[0090] Or, the silver member was adhered (supported, adsorbed or bonded)
to the resulting porous carbon material-B by using a method different
from that of the above case. Specifically, 0.215 g of porous carbon
material-B was added to 1.33 mmol/l of 15 ml of a silver nitrate aqueous
solution, and the stirring was carried out for 30 minutes. After that,
after the heating was carried out at 100.degree. C. and the boiling or
the like was confirmed, 20 mmol/l of 5 ml of a trisodium acid citrate
aqueous solution was dropped, and the reflux flow was carried out for 15
minutes. Also, after the resulting powder was filtered by using a filter
and was then rinsed by using distilled water, the drying was carried out
at 120.degree. C., thereby obtaining the fungicide of Example 1-B.
[0091] In addition, the porous carbon material-B was used as Comparative
Example 1 for various kinds of tests.
[0092] The element analysis about Example 1-A, Example 1-B, and
Comparative Example 1 was carried out based on an energy dispersion
method by using an energy dispersive X-ray analyzer. The analysis results
are shown in Table 1.
TABLE-US-00001
TABLE 1
Example 1 Example 2 Comparative Example 1
Element Mass % At. % Mass % At. % Mass % At. %
C 98.84 99.74 91.60 94.23 97.36 98.62
N -- -- 6.35 5.38 -- --
O -- -- -- -- 1.51 1.12
F 0.07 0.04 -- -- -- --
Na -- -- 0.01 0.01 -- --
Mg -- -- -- -- 0.01 0.01
Al -- -- -- -- -- --
Si 0.17 0.07 0.10 0.04 0.19 0.08
P 0.01 -- 0.02 0.01 -- --
S -- -- -- -- 0.03 0.01
Cl -- -- -- -- -- --
K -- -- -- -- 0.02 --
Ca -- -- -- -- 0.05 0.01
Sc -- -- -- -- 0.05 0.01
Ti -- -- -- -- 0.03 0.01
V -- -- 0.04 0.01 0.06 0.02
Cr -- -- 0.02 0.01 -- --
Mn 0.04 0.01 -- -- -- --
Fe -- -- 0.04 0.01 0.03 0.01
Co -- -- -- -- 0.02 --
Ni 0.04 0.01 0.11 0.02 0.01 --
Cu -- -- 0.27 0.05 0.12 0.02
Zn 0.09 0.02 0.09 0.02 0.25 0.05
Ga 0.26 0.04 0.66 0.11 -- --
Ge 0.14 0.02 0.35 0.06 0.01 --
As 0.12 0.02 0.14 0.02 0.06 0.01
Se -- -- -- -- 0.08 0.01
Br -- -- -- -- 0.06 0.01
Ag 0.21 0.02 0.19 0.02 0.06 0.01
Total 100 100 100 100 100 100
[0093] Since the composition ratio of silver is increased in each of the
fungicides of Example 1-A and Example 1-B, it is estimated that the
silver member was adhered (supported, adsorbed or bonded) to the porous
carbon material by carrying out the silver precipitating treatment either
in [Process-110A] or in [Process-110B].
[0094] FIG. 1 shows electron microscope images of the fungicide of Example
1-A, Example 1-B, and the specimen of Comparative Example 1. A situation
in which in each of the fungicides of Example 1-A and Example 1-B, the
fine particles each having a particle size of about several tens of
nanometer were precipitated was confirmed from these electron microscope
images.
[0095] In addition, identification of the product, and an estimation of
the particle size (refer to FIGS. 2A, 2B, 2C, and 2D) were carried out
based on the X-ray diffraction analysis. Here, an X-ray diffraction
system (RINT-TTRII) manufactured by RIGAKU CORPORATION was used, and a
Cu--K.alpha. ray was used as an X-ray source. It is noted that a
wavelength is 0.15405 nm. In addition, an applied voltage was set as 50
kV, and a scanning step was set as 0.04.degree.. Diffraction lines which
appear in the standard data of Ag could be confirmed from each of the
fungicides of Example 1-A and Example 1-B, and thus it was suggested from
this confirmation that a complex of carbon and Ag was formed. In
addition, it was found out that from a Scherrer's equation, the particle
size of precipitated silver is about 40 nm in each of the fungicides of
Example 1-A and Example 1-B.
[0096] BELSORP-mini (manufactured by BEL JAPAN INC.) was used as a
measurement instrument for obtaining the value of the specific surface
area, and the fine pore volume, and a test for adsorbing and desorbing
nitrogen was carried out.
[0097] With regard to the measurement condition, a measurement equilibrium
relative pressure (p/p.sub.0) was set in the range of 0.01 to 0.99. Also,
the value of the specific surface area, and the fine pore volume was
calculated based on the BELSORP analysis software. In addition, the test
for adsorbing and desorbing nitrogen was carried out by using the
measurement instrument described above, thereby calculating the fine pore
diameter distribution of the meso fine pores and the micro fine pores
based on both the BJH method and the MP method using the BELSORP analysis
software. It is noted that in Example and Comparative Example as well
which will be described later, the value of the specific surface area and
the fine pore volume, and the fine pore diameter distribution of the meso
fine pores and the micro fine pores were measured by using the same
method as that in the above case. In addition, analysis software that
comes with the automatic specific surface area/fine pore distribution
measuring apparatus "BELSORP-MAX" manufactured by BEL JAPAN, INC. was
used for the analysis based on the non localized density functional
theory method. It is noted that for the measurement, drying was carried
out at 200.degree. C. for 3 hours as a pretreatment for a specimen.
[0098] With regard to the fungicides of Example 1-A and Example 1-B, and
the specimen of Comparative Example 1 (porous carbon material-B), the
value of the specific surface area, and the fine pore volume were
measured, and as a result, the results shown in Table 2 were obtained. In
addition, the fine pore diameter distribution of the meso fine pores and
the micro fine pores was measured, and as a result, the results shown in
FIGS. 3A and 3B were obtained. It is noted that in table 1, "specific
surface area" and "entire fine pore volume" represent the specific
surface area (unit: m.sup.2/g) and the entire fine pore volume based on
the nitrogen BET method, respectively, and "BJH(T)" and "MP(T)" represent
the volume of the cumulative fine pore volume (unit: m.sup.2/g) based on
the BJH method, and the MP method, respectively. In addition, FIG. 4
shows the measurement results of the fine pore diameter distributions
about Example 1-A, Example 1-B and Comparative Example 1 which are
obtained by utilizing the non localized density functional theory method.
In this case, the rate of the total of the volumes of the fine pores
having the fine pore diameters in the range of 3 to 20 nm in the total
volume of all the fine pores was as follows. It is noted that since the
porous carbon material-B is prepared for Comparative Example 1, a large
difference in rate of the total of the volumes of the fine pores between
Example 1-A and Example 1-B, and Comparative Example 1 is not recognized
so much.
[0099] Example 1-A: 0.435 (total of volumes of all fine pores: 1.381
cm.sup.3/g)
[0100] Example 1-B: 0.538 (total of volumes of all fine pores: 1.293
cm.sup.3/g)
[0101] Comparative Example 1: 0.435 (total of volumes of all fine pores:
1.533 cm.sup.3/g)
[Table 2]
[Example 1-A]
[0102] Specific surface area: 1,169
[0103] Fine pore volume: 1.04
[0104] BJT(T): 0.64
[0105] MP(T): 0.50
[Example 1-B]
[0106] Specific surface area: 1,217
[0107] Fine pore volume: 1.08
[0108] BJT(T): 0.66
[0109] MP(T): 0.52
[Comparative Example 1 (porous carbon material-B)]
[0110] Specific surface area: 1,300
[0111] Fine pore volume: 1.16
[0112] BJT(T): 0.76
[0113] MP(T): 0.48
[Porous Carbon Material-A]
[0114] Specific surface area: 566
[0115] Fine pore volume: 0.60
[0116] BJT(T): 0.47
[0117] MP(T): 0.17
[0118] The value of the specific surface area and the entire fine pore
volume, the fine pore volume are smaller in each of the fungicides of
Example 1-A and Example 1-B for which the compounding treatment was
carried out than in the specimen of Comparative Example 1 for which no
compounding treatment was carried out. It is thought that this
measurement result results from that by carrying out the compounding
treatment, the fine pores of the porous carbon material were filled up by
adhesion (precipitation) of the silver particles, or the weight was
increased by adhesion (precipitation) of the silver particles.
[0119] From FIGS. 3A and 3B, the decrease in fine pore volume was totally
recognized. In particular, in a region of the meso fine pores shown in
FIG. 3A, the decrease in fine pore volume was remarkably confined in each
of the fungicides of Example 1-A and Example 1-B as compared with the
case of Comparative Example 1. This is thought to result from the
precipitation of the functional material.
[0120] In addition, in each of the porous carbon material complexes of
Example 1-A and Example 1-B, the content rate of silicon (Si) was
remarkably decreased. As a result, it was suggested that the porous
carbon material precursor is treated by using the acid to remove away the
silicon components such as the silicon dioxide contained therein, which
contributes to the increase in value of the specific surface area. In
addition, it was confirmed that the number of meso fine pores and micro
fine pores is increased by carrying out the treatment using the acid.
This also applies to Example which will be described later. Also, the
same results were obtained in the porous carbon material as well which
was obtained by carrying out the treatment using the alkali (base) such
as a sodium hydroxide aqueous solution instead of using a hydrofluoric
acid aqueous solution.
[0121] In the fungicide of Example 1, the porous carbon material in which
the value of the specific surface area based on the nitrogen BET method
was equal to or larger than 10 m.sup.2/g, the porous carbon material,
specifically, the content rate of silicon was equal to or smaller than 1
wt %, and the volume of the fine pore based on both the BJH method and
the MP method was equal to or larger than 0.1 cm.sup.3/g was used, and
the silver material was adhered to the porous carbon material concerned,
whereby it was possible to increase the amount of silver material adhered
per unit weight of the porous carbon material. Thus, it was possible to
obtain the high odor eliminating capacity and the high sterilization
effect. Here, the fungicide of Example 1 can also be utilized as a
deodorant product, a deodorizer, an antimicrobial agent, or a preserving
agent.
Example 2
[0122] Example 2 relates to a photo catalytic composite material of the
embodiment of the present invention. The photo catalytic composite
material of Example 2 (or, a depurative based on the photo catalytic
composite material) includes:
[0123] (A) a porous carbon material, specifically, having a plant-derived
material containing therein silicon as a raw material, more specifically,
a porous carbon material having a plant-derived material containing
therein silicon having a content rate of 5 wt % or more as a raw
material, the content rate of silicon being equal to or smaller than 1 wt
%; and
[0124] (B) a photo catalytic material adhered to the porous carbon
material,
[0125] in this case, a value of a specific surface area based on the
nitrogen BET method is equal to or larger than 10 m.sup.2/g, and a volume
of a fine pore based on both the BJH method and the MP method is equal to
or larger than 1 cm.sup.3/g, also, the photo catalytic material is
composed of a titanium oxide doped either with a cation or with an anion.
[0126] Or, the photo catalytic composite material (or the depurative based
on the photo catalytic composite material) of Example 2 includes:
[0127] (A) a porous carbon material; and
[0128] (B) a photo catalytic material adhered to the porous carbon
material, and
[0129] the photo catalytic material is composed of a titanium oxide doped
either with a cation or with an anion. Also, the value of the specific
surface area based on the nitrogen BET method is equal to or larger than
10 m.sup.2/g, and the total of the volumes of the fine pores having the
diameters in the range of 1.times.10.sup.-9 to 3.times.10.sup.-7 m
obtained by utilizing the non localized density functional theory method
is equal to or larger than 0.1 m.sup.3/g. Or, in the photo catalytic
composite material (or the depurative based on the p
hoto catalytic
composite material) of Example 2, the value of the specific surface area
based on the nitrogen BET method is equal to or larger than 10 m.sup.2/g,
and the rate of the total of the volumes of the fine pores having at
least one peak in the range of 3 to 20 nm, and having the fine pore
diameters in the range of 3 to 20 nm in the fine pore diameter
distribution obtained by utilizing the non localized density functional
theory method is equal to or larger than 0.2 of the total of the volumes
of all the fine pores.
[0130] Here, in Example 2, as has been described, the photo catalytic
material (functional material) is composed of the titanium oxide
(TiO.sub.2) functioning as a photo catalyst. The titanium oxide is
adhered (supported, adsorbed or bonded) to the porous carbon material. As
a result, the porous carbon material complex is given a charge separation
property, an ultraviolet ray absorption property, and a catalyst
property. Thus, the photo catalytic composite material can be used as a
harmful material decomposition agent, and a harmful material remover
which can be semi-permanently used due to the photo catalytic effect. In
addition, since the titanium oxide is doped either with the cation or
with the anion, for example, the titanium oxide can adsorb an energy of a
light having a wavelength of 200 to 600 nm, or an energy of a visible
light. It is noted that a conceptual view of the adsorption of the energy
is shown in FIG. 5. In addition, light absorption characteristics of the
titanium oxide (TiO.sub.2) are shown in FIG. 6.
[0131] Although in Example 2, the functional material composed of the
titanium oxide doped either with the cation or with the anion was adhered
(supported, adsorbed or bonded) to the porous carbon material-B descried
above, concretely, the compounding treatment was carried out as follows.
[0132] That is to say, 0.5 g of the porous carbon material-B, 4.57 ml of
an acetic acid, and a suitable amount of tetraisopropyl ortho-titanate
(TIPO) were added to 100 ml of ethanol, and the stirring was carried out
for 1 hour. After that, centrifugal separation was carried out, a
supernatant liquid was discarded, a small amount of ethanol was added to
a material in a solid phase and 100 ml of pure water was added by small
and small while an ultrasonic wave was applied to the pure water. After
that, the centrifugal separation was carried out again, and the resulting
material in the solid phase was dried at 100.degree. C. It is noted that
the specimen obtained in this stage was used as a specimen of
"Comparative Example 2." Next, crystal growth was carried out at
400.degree. C. in an ammonia gas atmosphere to dope the titanium oxide
with an anion composed of nitrogen, thereby making it possible to obtain
the photo catalytic composite material (depurative) of Example 2-A.
[0133] Or, an aqueous solution was prepared in which 0.24 g of
FeCl.sub.3.6H.sub.2O was dissolved in 150 ml of pure water, and pH 2 was
obtained by using a hydrochloric acid. Also, after the photo catalytic
composite material thus obtained of Example 2-A was dispersed in the
aqueous solution, and the stirring was carried out for 1 hour, the photo
catalytic composite material was filtered by using a filter, and was
rinsed in a distilled water. After that, the photo catalytic composite
material was dried at 150.degree. C., thereby making it possible to
obtain a photo catalytic composite material (depurative) of Example 2-B.
Note that, such a treatment is a treatment which is carried out for the
purpose of doping the titanium oxide with an iron ion as the cation.
[0134] It was possible to confirm that the titanium oxide (TiO.sub.2) is
contained in each of the specimens of Example 2-A and Example 2-B by
carrying out the X-ray diffraction analysis (XRD). In addition, the
specific surface area and the entire fine pore volume were measured based
on the nitrogen BET method, the BJH method, and the MP method, and the
measurement results are shown in Table 3. In addition, results of
measurements of the fine porous (meso fine pores) are shown in FIG. 7. In
addition, FIG. 8 shows the measurement results of the fine pore diameter
distributions about Example 2-A and Example 2-B which are obtained by
utilizing the non localized density functional theory method. In this
case, the rate of the total of the volumes of the fine pores having the
fine pore diameters in the range of 3 to 20 nm in the total volume of all
the fine pores was as follows.
[0135] Example 2-A: 0.561
[0136] Example 2-B: 0.367
TABLE-US-00002
TABLE 3
Example 2-A Example 2-B
Content rate of (TiO.sub.2) (wt%) 23.1 29.1
Specific surface area (m.sup.2/g) 1,235 934
Entire fine pore volume (m.sup.3/g) 0.9404 0.7088
JBT (T) (m.sup.3/g) 0.5468 0.4254
MP (T) (m.sup.3/g) 0.4993 0.4439
NFDLT (T) (m.sup.3/g) 1.1354 0.9796
[0137] For the evaluation, 13 mg of the photo catalytic composite material
of Example 2-A, and 13 mg of the specimen of Comparative Example 2 were
each added to 50 ml of 0.08 mmol/l of a tannic acid aqueous solution.
After a lapse of 24 hours, the pseudo solar light was radiated thereto.
The radiation results are shown in FIG. 9. Thus, in the case of Example
2-A, it was possible to reliably decompose the tannic acid aqueous
solution.
[0138] In addition, for the evaluation, 15 mg of the photo catalytic
composite material of Example 2-B, and 15 mg of the specimen of
Comparative Example 2 were each added to 50 ml of 0.15 mml/l of a methyl
orange aqueous solution, and the pseudo solar light was radiated thereto.
The radiation results are shown in FIG. 10. Thus, in the case of Example
2-B, it was possible to confirm that after a lapse of 8 hours from start
of the radiation of the pseudo solar light, almost methyl orange was
decomposed.
[0139] In addition, an experiment was carried out such that 1.5 mg of the
specimen (optical catalytic composite material) of Example 2-B, and 1.5
mg of a porous carbon material-B (Comparative Example 2') were each added
to 5 ml of water, 100 .mu.g of micro-cystine was charged thereto every 24
hours, and the radiation and blocking of the pseudo solar light were
repetitively carried out every 12 hours. The experimental results are
shown in FIG. 11A. In the case of the porous carbon material-B
(Comparative Example 2'), micro-cystine was not approximately absorbed at
the third round of charging, whereas in the case of the specimen of
Example 2-B, a sharp adsorption was observed many times. From the
experiment results, it was possible to confirm that in the specimen of
Example 2-B, micro-cystine is taken in the meso fine pores, and is
thereafter decomposed by the radiation of the pseudo solar light. This is
shown in a conceptual view of FIG. 11B. Note that, in FIG. 11B, a
sawtooth waveform indicated by a solid line shows the results of the
experiment about the specimen of Example 2-B, and a waveform indicated by
a dotted line shows the results of the experiment about the specimen of
Comparative Example 2'.
[0140] The porous carbon material in Example 2 is more specifically, the
natural product-derived environment conciliatory material, and the fine
structure thereof is obtained by treating the silicon components (silicon
oxides) previously contained in the raw material as the plant-derived
material by using either the acid or alkali to remove away the silicon
components. Therefore, the fine pore has the size and the meso region (in
the range of 2 to 50 nm) which cannot be realized in the existing
activated carbon. In addition, the arrangement of the fine pores
maintains the biological body regularity which the plant has. In the
optical catalytic composite material of Example 2, by such a fine pore
size and arrangement, the photo catalytic material can be very
effectively adhered to the porous carbon material, and thus the
decomposition based on the photo catalytic action can be effectively
caused. In addition, it is thought that even in the depurative based on
the photo catalytic composite material of Example 2 as the environment
purifying material, such a fine pore size and arrangement effectively
acts on the adsorption of the harmful materials. At the same time, the
photo catalytic material can be very effectively adhered to the porous
carbon material, and thus the decomposition and the detoxification in the
photo catalytic action can be effectively caused. In addition, the
diffusion of the harmful materials in the inside of the depurative is
promoted, and thus the decomposition based on the optical catalytic
action can be more effectively caused, and thus the purification of the
water and the purification of the air can be very effectively carried
out. In addition, since the photo catalytic composite material of Example
2 can absorb the energy of the visible light, it is possible to provide
the photo catalytic composite material showing the superior decomposition
reaction.
Example 3
[0141] Example 3 relates to an adsorbent and a depurative of the
embodiment of the present invention. The adsorbent and the depurative of
Example 3 include:
[0142] (A) a p
hoto catalytic composite material, specifically, a porous
carbon material having a plant-derived material containing therein
silicon as a raw material, more specifically, a porous carbon material
having a plant-derived material containing therein silicon having a
content rate of 5 wt % or more as a raw material, the content rate of
silicon being equal to or smaller than 1 wt %; and
[0143] (B) an organic material adhered to the porous carbon material,
[0144] in this case, a value of a specific surface area based on a
nitrogen BET method is equal to or larger than 10 m.sup.2/g, and a volume
of a fine pore based on both the BJH method and the MP method is equal to
or larger than 0.1 cm.sup.3/g,
[0145] also, the organic material adsorbs a metal.
[0146] Or, the adsorbent or the depurative of Example 3 includes:
[0147] (A) a porous carbon material; and
[0148] (B) a photo catalytic material adhered to the porous carbon
material, and
[0149] an organic material adsorbs a metal. Also, the value of the
specific surface area based on the nitrogen BET method is equal to or
larger than 10 m.sup.2/g, and the total of the volumes of the fine pores
having the diameters in the range of 1.times.10.sup.-9 to
3.times.10.sup.-7 m obtained by utilizing the non localized density
functional theory method is equal to or larger than 0.1 cm.sup.3/g. Or,
in the adsorbent or the depurative of Example 3, the value of the
specific surface area based on the nitrogen BET method is equal to or
larger than 10 m.sup.2/g, and the rate of the total of the volumes of the
fine pores having at least one peak in the range of 3 to 20 nm, and
having the fine pore diameters in the range of 3 to 20 nm in the fine
pore diameter distribution obtained by utilizing the non localized
density functional theory method is equal to or larger than 0.2 of the
total of the volumes of all the fine pores.
[0150] In Example 3 polyethylene imine was used as the organic material. A
state in which polyethylene imine is adhered (supported, adsorbed or
bonded) to the porous carbon material is schematically shown in FIG. 12.
In addition, a chromium (Cr) ion was adsorbed as the metal. In the
adsorbent and the depurative of Example 3, 0.3 g of the porous carbon
material-B described above, and 1.5 g of polyethylene imine were
dispersed in 100 ml of pure water, and the stirring was carried out for 1
hour, thereby adhering (supporting, adsorbing or bonding) polyethylene
imine to the fine pores in the meso region of the porous carbon
material-B. After that, the material in a solid phase which was obtained
through the filtering was charged in an aqueous solution in which 0.5 g
of FeCl.sub.3.6H.sub.2O was dissolved in 100 ml of pure water, and the
stirring was carried out for 1 hour. Also, after resulting powder was
filtered by using a filter, and was then rinsed by using distilled water,
the drying was carried out at 120.degree. C., thereby obtaining the
adsorbent and the depurative of Example 3. It is noted that the treatment
using FeCl.sub.3.6H.sub.2O is carried out in such a manner, thereby
making it possible to enhance the ion exchange capacity. This state is
schematically shown in FIG. 13.
[0151] After 10 mg of the specimen of Example 3, and 10 mg of commercially
available activated carbon (Comparative Example 3) were dispersed in 5 ml
of each of various concentrations of potassium chromate, and the stirring
was carried out for 1 hour, the absorbance was measured. The measurement
results are shown in FIG. 14. It was possible to confirm that the
adsorbent and the depurative of Example 3 (indicated by "A" in FIG. 14)
have the adsorptive performance which is 20 times as large as that of the
commercially available activated carbon (indicated by "B" in FIG. 14).
That is to say, the adsorbent and the depurative of Example 3 can
effectively adsorb the metal (such as the metal atom or the metal ion)
because the organic material is adhered (supported, adsorbed or bonded)
to the porous carbon material. It is noted that a state in which the
adsorbent and the depurative of Example 3 adsorb a potassium chromate ion
is schematically shown in FIG. 15. In addition, the specific surface area
and the entire fine pore volume were measured based on the nitrogen BET
method, the BJH method and the MP method, and the measurement results are
shown in Table 4. In addition, FIG. 16 shows the measurement results of
the fine pore diameter distributions about Example 3 and Comparative
Example 3 which are obtained by utilizing the non localized density
functional theory method. In this case, the rate of the total of the
volumes of the fine pores having the fine pore diameters in the range of
3 to 20 nm in the total volume of all the fine pores was as follows.
[0152] Example 3: 0.415
[0153] Comparative Example 3: 0.134
TABLE-US-00003
TABLE 4
Examples 3 Comparative Example 3
Specific surface area (m.sup.2/g) 957 1,184
Entire fine pore volume (m.sup.3/g) 0.7817 0.05731
JBT (T) (m.sup.3/g) 0.4948 0.0816
MP (T) (m.sup.3/g) 0.3743 0.5702
NFDLT (T) (m.sup.3/g) 1.0511 0.7557
[0154] Although the present invention has been described so far based on
Examples, the present invention is by no means limited thereto, and
various kinds of changes can be made. Although in each of Examples 1 to
4, the description has been given with respect to the case where the rice
hull is used as the raw material of the porous carbon material, any other
suitable plant may also be used as the raw material. Here, a straw, a
reed, or a stalk brown seaweed (kukiwakame), a vascular plant, a
pteridophyte or a bryophyte which is vegetated on the land, an alga or a
sea alga can be given as any other suitable plant. These materials may be
used either in the form of singularity or in the form of multiple kinds
of materials mixed with one another.
[0155] Specifically, for example, a straw of a rice plant (for example,
Isehikari from Kagoshima Prefecture) is used as the plant-derived
material as the raw material of the porous carbon material. Also, the
straw as the raw material is carbonized to be transformed into the
carbonaceous material (porous carbon material precursor), and the
resulting porous carbon material precursor is then subjected to the acid
treatment, thereby making it possible to obtain the porous carbon
material. Or, the graminaceous reed is used as the plant-derived material
as the raw material of the porous carbon material, and graminaceous reed
as the raw material is carbonized to be transformed into the carbonaceous
material (porous carbon material precursor). Next, the resulting porous
carbon material precursor is subjected to the acid treatment, thereby
making it possible to obtain the porous carbon material. In addition, the
same results were obtained even in the porous carbon material which was
obtained in the treatment using an alkali (base) such as a sodium hydrate
liquid solution instead of using a hydrofluoric acid liquid solution. It
should be noted that a method of manufacturing the porous carbon material
complex can be made same to that in each of Example 1 to Example 3.
[0156] Or, the stalk brown seaweed (kukiwakame) (from Sanriku in Iwate
Prefecture) is used as the plant-derived material as the raw material of
the porous carbon material, and the stalk brown seaweed (kukiwakame) as
the raw material is carbonized to be transformed into the carbonaceous
material (porous carbon material precursor). Next, the resulting porous
carbon material precursor is subjected to the acid treatment, thereby
making it possible to obtain the porous carbon material. Specifically,
firstly, for example, the stalk brown seaweed (kukiwakame) is heated at a
temperature of about 500.degree. C. to be carbonized. It is noted that
before the heating, for example, the stalk brown seaweed (kukiwakame) as
the raw material may be treated by using alcohol. A method of dipping the
stalk brown seaweed (kukiwakame) as the raw material in ethyl alcohol or
the like is given as the concrete treatment method. As a result, it is
possible to reduce water contained in the raw material, and it is also
possible to elute elements other than carbon, and the mineral components
which are all contained in the porous carbon material finally obtained.
In addition, by carrying out the treatment using alcohol, it is possible
to suppress the generation of gas in a phase of the carbonization. More
specifically, the stalk brown seaweed (kukiwakame) is dipped in ethyl
alcohol for 48 hours. It is noted that an ultrasonic treatment is
preferably carried out in ethyl alcohol. Next, the stalk brown seaweed
(kukiwakame) is heated at 500.degree. C. for 5 hours in a nitrogen
gas-flow to be carbonized, thereby obtaining the carbide. It is noted
that by carrying out such a treatment (preliminary carbonization
treatment), the tar component which will be generated during the next
carbonization can be either reduced or removed away. After that, 10 g of
the carbide is put in a crucible made of alumina, and a temperature of 10
g of the carbide is made to rise to 1,000.degree. C. at a rate of
temperature rise of 5.degree. C./minute in the nitrogen gas-flow (10
l/minute). Also, after the carbide is carbonized at 1,000.degree. C. for
5 hour to be transformed into the carbonaceous material (porous carbon
material precursor), the resulting porous carbon material precursor is
cooled to a room temperature. It is noted that during the carbonization
and the cooling, the nitrogen gas is continuously flowed. Next, after the
porous carbon material precursor is dipped in 46 vol % hydrofluoric acid
aqueous solution through the night, thereby carrying out the acid
treatment, the porous carbon material is rinsed until pH 7 is obtained by
using water and ethyl alcohol. Also, finally, the drying is carried out,
thereby making it possible to obtain the porous carbon material. After
that, the compounding treatment and the activation treatment which were
described in each of Example 1 to Example 3 have to be carried out.
[0157] The present application contains subject matter related to that
disclosed in Japanese Priority Patent Application JP 2011-009456 filed
with the Japan Patent Office on Jan. 20, 2011, the entire content of
which is hereby incorporated by reference.
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