JP2004313830A - Photochemical reaction method, treatment method and treatment apparatus for soil or incineration ash - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photochemical reaction which can be utilized for various chemical reactions, is low in cost and is highly efficient. <P>SOLUTION: The photochemical reaction method comprises photoexciting the reaction molecules in a solid phase by irradiating the same with light having energy to excite the reaction molecules and acting a catalyst on the excited reaction molecules to cause reaction. According thereto, the reactivity of the reaction molecules is enhanced by irradiating the reaction molecules with the light to put the reaction molecules on an excited state and to raise the reactivity up, and an activation barrier of the reaction can be lowered by acting the catalyst on the reaction molecules in the excited state. The rate of the reaction can therefore be improved and the smooth progression of the reaction is made possible. The photochemical reaction method can be utilized for detoxification treatment of the soil or incineration ash contaminated with harmful substances, for example, dioxins. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００７０】
実施例１、実施例２、実施例３及び実施例４より、光照射を行い、かつ、触媒を存在させることにより、分解反応が進行していることが判る。
比較例１、比較例２、比較例５及び比較例８より、触媒が存在しても光照射を行わない場合には、反応が進行していないことが判る。
比較例３、比較例６及び比較例９より、光照射を行っても触媒が存在しない場合には、反応が進行していないことが判る。
比較例４、比較例７及び比較例１０より、触媒が存在せず、かつ、光照射も行わない場合には、反応が進行していないことが判る。
【００７１】
以上の結果から、反応分子を励起させるエネルギーを有する光を照射し、触媒を作用させることによって反応を高効率で進行させることができることが判った。すなわち、反応分子を直接光分解する程のエネルギーまたは触媒を励起させる程のエネルギーを有する光を用いずとも、反応分子の吸収波長領域程度の比較的低いエネルギーを有する光を照射して反応分子を励起させ、かつ、光触媒のように触媒を光励起させなくとも励起した反応分子に触媒を作用させることで反応を進行させることができる。これより、低コストで高効率な化学反応が実現可能である。
【００７２】
【発明の効果】
以上説明したように、反応分子に光を照射して励起させることにより反応分子の反応性を高めるとともに、励起した反応分子に触媒を作用させることで活性化障壁を下げることができる。よって、低エネルギーで反応を進行させることが可能であり、例えば、ダイオキシン類などの有害物質を低コスト、かつ効率的に分解処理することができる。
【図面の簡単な説明】
【図１】光化学反応装置の説明に供する概略構成図。
【図２】光化学反応の説明に供する図面。
【符号の説明】
１０ 光化学反応装置
１１ 光化学反応槽
１２ 光源
１３ 供給装置
１４ 触媒供給装置
１５ 排出装置[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a photochemical reaction using a catalyst. More specifically, regarding the reaction of organic compounds using a photochemical reaction, furthermore, harmful substances such as dioxins contained in a solid phase such as soil and incinerated ash are treated using a photochemical reaction method. The present invention relates to a processing method and a soil or incineration ash processing apparatus.
[0002]
[Prior art]
Until now, many documents have been disclosed on chemical reaction processes using light energy. In particular, for example, the following documents have been reported as toxic substance treatments, and each has the following problems.
[0003]
(1) Japanese Patent Application Laid-Open No. 2000-5562 (Patent Document 1) discloses that an organic chlorine compound (for example, A method for decomposing trichlorethylene, tetrachloroethylene, etc.) is disclosed.
[0004]
The treatment method according to Patent Literature 1 decomposes an organic chlorine compound with an oxidizing agent and / or a catalyst, and further treats the compound with irradiation of ultraviolet rays. As described above, an organic chlorinated compound is treated by an individual effect of an oxidizing agent, a catalyst, or ultraviolet light, and no technical idea about the correlation between the oxidizing agent, the catalyst, and the ultraviolet light is described. Focusing on the effect of ultraviolet light, since it is directly used for photodecomposition of organic chlorine compounds (ultraviolet light oxidative decomposition), high-energy and high-energy ultraviolet light is required, and energy loss is large.
[0005]
(2) Japanese Patent Application Laid-Open No. 2002-18240 (Patent Document 2) discloses a photodecomposition reaction step of decomposing harmful organic substances by irradiating exhaust gas with ultraviolet light having a vacuum ultraviolet region to an exhaust gas, and a photocatalyst using ultraviolet light not having a vacuum ultraviolet region. A photocatalytic reaction step of decomposing harmful organic substances by contacting the exhaust gas that has passed through the previous process with a photocatalyst to decompose harmful organic substances, thereby detoxifying harmful organic compounds (eg, trichloroethane, etc.) contained in the exhaust gas. It has been disclosed.
[0006]
According to Patent Literature 2, in the photodecomposition reaction step, vacuum ultraviolet light having low luminous efficiency and extremely low transmittance in the air is used, so that it is not used for decomposition of harmful organic substances in the input energy. The rate of heat energy consumption is high and the efficiency is low, and sufficient decomposition efficiency cannot be obtained with only one treatment step. Further, in the photocatalytic reaction step, the decomposition treatment is performed by the contact reaction of harmful organic substances to the photoexcited catalyst surface using a photocatalyst, but only the examples using titanium dioxide specifically as the photocatalyst are described. Notwithstanding, the reaction is limited to those in which the characteristics of titanium dioxide can be used and cannot be applied to various harmful substances.
[0007]
(3) Japanese Patent Application Laid-Open No. 11-335204 (Patent Document 3) discloses that a rod made of a transparent material is placed on soil, light rays are condensed from an exposed portion, and guided into the soil along the rod. A method of irradiating a photocatalyst carried on the surface of the rod-shaped body to sterilize and sterilize nearby soil by a photocatalytic reaction is disclosed.
[0008]
According to Patent Literature 3, the cost is low because sunlight can be used as a light source, but it is difficult to secure the sunlight depending on fluctuations in weather conditions, so that the reliability is poor and the titanium oxide as a photocatalyst is excited. The reaction efficiency is low because light (ultraviolet light) having sufficient energy to reach the ground surface is limited. Another problem is that the bacteria can be sterilized only in the vicinity of the rod-shaped body carrying the photocatalyst.
[0009]
As described above, many documents disclose the decomposition treatment of harmful substances using light energy as it is or the decomposition treatment of harmful substances using photoexcitation of a catalyst such as titanium dioxide.
[0010]
[Patent Document 1]
JP-A-2000-5562
[Patent Document 2]
JP 2002-18240A
[Patent Document 3]
JP-A-11-335204
[0011]
[Problems to be solved by the invention]
That is, practical techniques of chemical reactions using light energy can be roughly classified into the following two types, and each has the following problems.
[0012]
{Circle around (1)} A method of directly decomposing reactive molecules with light energy. In this method, high-energy light such as vacuum ultraviolet light needs to be used because light energy is used to break chemical bonds in molecules (that is, electrons existing in bonding orbitals are excited to antibonding orbitals). There is. That is, in consideration of the breaking of the bond due to only the light energy, generally, a plurality of electrons bonded at a higher energy (deep energy level) are more than a plurality of electrons bonded at a lower energy (shallow energy level). Since it is effective to excite electrons to antibonding orbitals, it is necessary to irradiate high-energy and large-energy light that can release multiple electrons bound to the deep energy level. Energy consumption is large and economically inferior.
[0013]
{Circle around (2)} A method of reacting reactive molecules using a photocatalyst. In this method, since light energy is used to excite the photocatalyst, light having constant energy enough to excite the photocatalyst is always required regardless of the chemical reaction, and the energy efficiency is low. Also, in this case, the excited photocatalyst is often a multi-stage reaction in which the reaction proceeds via a hydroxyl radical, superoxide ion, or the like generated by reaction with water or the like, and the energy required for photoexcitation of the catalyst is: It is larger than the energy required for the reaction and has low energy efficiency.
[0014]
In addition, available reactions are limited. That is, at present, photocatalysts that can be used with practical efficiency are almost limited to those mainly using titanium dioxide, and irradiation with light (ultraviolet light) corresponding to the energy gap of titanium dioxide is indispensable. It is generally difficult to use, so efficiency is low. In addition, since it is practically limited to those utilizing the properties of titanium dioxide, it cannot be used for reactions requiring energy equal to or more than the energy gap of titanium dioxide, and for reactions that proceed with energy less than that. In this case, the difference is wasted.
[0015]
Therefore, a low-cost and highly efficient chemical reaction that can be used for various chemical reactions is desired, and it is an object of the present invention to provide a reaction method.
[0016]
[Means for Solving the Problems]
In order to solve the above problems, the invention of the photochemical reaction method according to the first aspect of the present invention is to irradiate light having energy to excite a reactive molecule to photoexcit the reactive molecule in the solid phase, and to perform the excited reaction. It is characterized by reacting a molecule with a catalyst.
[0017]
According to this feature, the reactivity of the reactive molecule can be increased by exciting the reactive molecule, and further, the activation barrier can be lowered by causing a catalyst to act on the excited reactive molecule, so that the reaction rate can be improved. The reaction can proceed smoothly.
[0018]
The invention of the photochemical reaction method according to the second aspect of the present invention is characterized in that, in the first aspect, the reactive molecule is an organic halogen compound.
[0019]
Further, the invention of the photochemical reaction method according to the third aspect of the present invention is characterized in that, in the first aspect or the second aspect, the reactive molecule is contained in soil or incinerated ash. .
[0020]
According to the second and third aspects, for example, an organic halogen compound such as dioxins, which is an environmental pollutant contained in a solid phase such as soil or incineration ash, is oxidized or decomposed to increase efficiency. Can be removed.
[0021]
The photochemical reaction method according to a fourth aspect of the present invention is characterized in that, in any one of the first to third aspects, the catalyst is a metal oxide. .
[0022]
The photochemical reaction method according to a fifth aspect of the present invention is characterized in that, in any one of the first to third aspects, the catalyst is a soil component. According to this feature, for example, by irradiating predetermined light to soil contaminated with an organic halogen compound such as dioxins, it is possible to efficiently decompose and remove the organic halogen compound and the like as a pollutant. it can.
[0023]
Further, the invention of a method for treating soil or incineration ash according to the sixth aspect of the present invention uses the photochemical reaction method according to any one of the first to fifth aspects to utilize the soil or incineration ash. It is characterized by treating incinerated ash. According to this feature, soil or incinerated ash contaminated with harmful substances such as dioxins can be efficiently detoxified.
[0024]
Further, the invention of the soil or incineration ash treatment apparatus according to the seventh aspect of the present invention includes providing a light source for photo-exciting the reaction molecules in the reaction vessel, and irradiating the reaction molecules contained in the soil or incineration ash with light. And reacts the excited reaction molecules by causing the catalyst present in the reaction vessel to act on the excited reaction molecules. According to this feature, soil or incinerated ash contaminated with harmful substances such as dioxins can be detoxified.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
The photochemical reaction method of the present invention is carried out by irradiating light having energy to excite the reactive molecule to photoexcit the reactive molecule in the solid phase, and causing the excited reactive molecule to react with a catalyst.
[0026]
In the present invention, light energy is used to excite reactive molecules.
By irradiating the reaction molecules with light having sufficient energy to excite the reaction molecules, the reaction molecules are partially converted from a ground state in which the bonding orbitals are filled with electrons and a strong bond is formed. The excited state is excited to the antibonding orbital. That is, some of the electrons in the bonding orbital gain energy and move to a more reactive antibonding orbital. Since this excitation is generally one-electron excitation, the reaction can proceed with less energy than the energy at the time of photolysis of the reaction molecule. In addition, the irradiation light only needs to have enough energy to excite the individual reaction molecules, so that it is possible to reduce energy that is wasted in principle compared to the case of the photocatalyst.
[0027]
The excited state of the reaction molecule is generally higher in reactivity than the ground state reaction molecule, and thus the reaction can proceed with less energy than the ground state molecule. In addition, the activation barrier can be lowered by applying an appropriate catalyst to the reactive molecule in the excited state, so that the reaction can proceed more smoothly.
[0028]
That is, the reactivity is enhanced by photoexcitation of the reactive molecule, and the activation barrier is reduced by the catalytic action, whereby the reaction can proceed smoothly and a low-cost and highly efficient chemical reaction can be realized.
[0029]
The photochemical reaction in the present invention has a different reaction mechanism (for example, electrons move from the excited reaction molecule to the catalyst) from a normal catalytic reaction in which a reaction molecule in a ground state is reacted via a catalyst. It is conceivable that a desired reaction can be realized by appropriately selecting reaction conditions such as a light source, a catalyst, a reaction temperature, a pressure, and a coexisting substance. That is, the photochemical reaction in the present invention is applicable to reactions such as bond cleavage, isomerization (rearrangement), cycloaddition, ring closure, ring opening, addition, substitution, oxidation, reduction, synthesis, and decomposition. It is effective for a dehalogenation reaction, an oxidation reaction, and a decomposition reaction when the reactive molecule is an aromatic organic halogen compound. This is because, in the ground state, the electrons in the bonding orbitals are excited to the antibonding orbitals by light energy, so that the bonding strength of the carbon-chlorine bond and the specific carbon-carbon bond in the aromatic ring is weakened, resulting in a decomposition reaction. It is considered that the property is remarkably improved.
[0030]
The photochemical reaction according to the present invention can be effectively used for treating harmful substances such as dioxins existing in a solid phase such as soil or incineration ash. That is, the method can be effectively used as a soil or incineration ash treatment method for detoxifying soil or incineration ash containing harmful substances by utilizing a photochemical reaction.
[0031]
The reactive molecule is not particularly limited as long as it is a substance that is excited by the irradiated light. For example, harmful substances such as soil, organic compounds contained in incinerated ash, etc., aromatic organic compounds, and halogen-containing compounds Can be mentioned. Here, examples of the organic compound include a carbonyl compound, an alkane, an alkene, an aromatic hydrocarbon, a conjugated unsaturated carbonyl compound, a carboxylic acid, a halogen compound, a carbonitrile, an alcohol, an ether, a nitrogen-containing organic substance, a sulfur-containing organic substance, and a phosphorus-containing substance. Organic substances, silicon-containing organic substances, heteroaromatic compounds, organometallic complexes and the like can be mentioned.
[0032]
Furthermore, organic coloring substances such as blue dye No. 1, organic compounds such as aromatic compounds such as anthracene, organic chlorine compounds such as dioxins, precursors of dioxins such as benzenes or phenols, endocrine disrupting chemicals (so-called environmental hormones) And monocyclic or polycyclic aromatic halogen compounds. In particular, the aromatic ring organic compound is often excited by visible light due to a functional group, and can be excited relatively easily.
[0033]
Further, these reactive molecules may be contained in solids such as soil and incineration ash. That is, the present invention can be used as a soil or incineration ash treatment method for detoxifying soil or the like by decomposing harmful substances such as dioxins contained in a solid phase such as soil or incineration ash.
[0034]
The light for irradiating the reaction molecule only needs to have at least enough energy to excite the reaction molecule, and can be appropriately set according to the reaction molecule. Note that it is preferable to use light having energy which excites a reactive molecule but does not excite a catalyst.
[0035]
The light source is not particularly limited, but natural light or a desired artificial light source can be used. Natural light can be used when long-time exposure processing is possible or when processing is performed at low cost without using an artificial light source.
[0036]
Artificial light sources can be used when efficient processing is required in a relatively short period of time, including incoherent light sources (eg, xenon lamps, halogen lamps, mercury lamps, deuterium lamps, metal halide lamps, etc.) and wavelength selection. A highly coherent light source (eg, an excimer laser, an argon ion laser, a ruby laser, a semiconductor laser, or the like) can be used as appropriate depending on the reaction molecule. When a light source having high wavelength selectivity is used, the reaction molecules can be selectively excited to cause the reaction molecules to react selectively.
[0037]
For example, when the reaction molecule is a dioxin, an ultraviolet light source such as a mercury lamp can be selected since the dioxin has an absorption band in the ultraviolet region (that is, a wavelength region where light is excited). Conditions such as light irradiation time and light intensity can be appropriately set according to reaction conditions such as reaction molecules, reaction time, and reaction temperature.
[0038]
The energy (wavelength) at which the reaction molecule can be photoexcited is specific to the state of the reaction molecule, for example, 350 nm when the reaction molecule is a chlorine-free dioxin, 300 nm when the reaction molecule is a 4-chlorine dioxin, and 8 chlorine value. 400 nm for dioxins, 170 nm for chloroform / carbon tetrachloride, 180 nm for lower alcohols, around 300 nm for aldehydes, naphthalene / pyrene / phenanthrene condensed polycyclic aromatic In some cases, 300 to 400 nm, in the case of indigo, 620 nm, in the case of eosin, 520 nm, in the case of β-carotene, 480 nm, in the case of chlorophyll α, 660 nm, and in the case of zinc phthalocyanine / copper phthalocyanine / phthalocyanine, 7 00 nm, 620 nm for malachite green, 660 nm for methylene blue, around 630 nm for blue dye No. 1, around 400 nm for anthracene, and around 350 nm for 2,4,5-trichlorophenol , And so on.
[0039]
As the catalyst, any substance can be used without particular limitation as long as it has the effect of reducing the activation barrier between the electronic state of the excited reaction molecule and the desired product molecule. Also, the catalyst need not be a photocatalyst. Specific examples of preferred catalysts include, for example, Mg, Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Nb, Ru, Rh, Pd, Ag, Ta, W, Re. , Os, Ir, Pt, Au and the like, or a metal oxide thereof or a composite metal oxide thereof. Here, as the metal oxide, for example, magnesium oxide, aluminum oxide, silicon oxide, titanium oxide, vanadium oxide, chromium oxide, manganese oxide, iron oxide, cobalt oxide, nickel oxide, copper oxide, zinc oxide, zirconia, Niobium oxide, silver oxide, thallium oxide, tungsten oxide and the like, and as the composite metal oxide, for example, titanium, silicon, aluminum, platinum, ruthenium, niobium, tantalum, strontium, barium, sodium, potassium, tungsten, bismuth , Cerium, antimony, iridium, yttrium, gallium and the like.
[0040]
The catalyst preferably has a large contact area with the reaction molecule such as a powder or a particle (that is, a contact frequency with the reaction molecule is large). The catalyst is supported on a carrier such as zeolite or activated carbon. Those can also be used. Further, these catalysts are added so as to have a predetermined addition amount to the reaction target. The addition amount can be appropriately set according to reaction conditions such as a light source, a reaction molecule, a reaction temperature, and a reaction time.
[0041]
When the reaction target is a solid substance such as soil or incineration ash, the metal oxide or composite metal oxide contained therein can be used as a catalyst as it is. That is, since the metal oxide or the composite metal oxide contained in soil or incineration ash can be used as a catalyst as it is, soil, incineration ash or the like can be used as it is without adding a new catalyst. Here, examples of the metal oxide or composite metal oxide contained in soil and the like include magnesia, silica, alumina, titanium oxide, vanadium oxide, chromium oxide, manganese oxide, iron oxide, cobalt oxide, nickel oxide, copper oxide And zinc oxide. Further, the above metal, metal oxide or composite metal oxide can be added to soil or the like in order to promote the reaction. In this case, it is preferable to adjust the addition amount according to reaction conditions such as a light source, a reaction molecule, a reaction temperature, and a reaction time. Note that a solid metal oxide catalyst is preferable for decomposing the organic chlorine compound.
[0042]
Further, it is preferable to heat the reaction system between the excited reaction molecule and the catalyst. This removes water contained in the reaction target, allows the excited reaction molecules to exist for a longer time, and increases the frequency of contact with the catalyst. In addition, it is possible to promote the reaction more smoothly by promoting the excitation of the reaction molecule, and to further reduce the activation barrier of the reaction by increasing the activity of the catalyst. The heating temperature can be appropriately set according to the reaction conditions such as the catalyst, the reaction molecule, and the reaction time, and is, for example, about 50 ° C to 250 ° C, and preferably about 80 ° C to 150 ° C.
[0043]
Further, it is preferable to introduce oxygen into the reaction system. By introducing oxygen, the oxidation reaction of the reaction molecules in the reaction system can be promoted, and the oxidation reaction and decomposition reaction of harmful substances such as dioxins can be promptly performed. The oxygen concentration in the reaction system can be appropriately set according to the reaction conditions such as the reaction molecule, the reaction temperature, the reaction time, and the catalyst, and is, for example, about 0.1% to 30%, and 1% to 20%. The degree is preferred.
[0044]
Further, the reaction system is preferably stirred. By stirring the reaction system, the reaction molecules can be sufficiently irradiated with light, and the reaction molecules can be surely excited. Further, it is possible to increase the frequency of contact between the excited reaction molecules and the catalyst.
[0045]
FIG. 1 is a diagram showing a schematic configuration of a photochemical reaction apparatus 10 that treats and renders harmless a solid substance such as soil or incinerated ash.
[0046]
The soil treated by the photochemical reactor 10 includes, for example, volatile organic chlorine compounds such as trichloroethylene and tetrachloroethylene, dioxins (eg, polyhalogenated dibenzodioxin, etc.) and benzofuran used for washing electronic components and precision machinery. And harmful substances such as pesticides, organic coloring substances, endocrine disrupting chemicals and the like (eg, polyhalogenated dibenzofurans). Examples of incinerated ash include dioxins (eg, polyhalogenated dibenzodioxin) and benzofurans (eg, polyhalogenated) generated during incineration in an incinerator for treating municipal waste and industrial waste. Examples include substances containing harmful substances such as organic halogen compounds such as dibenzofuran.
[0047]
In FIG. 1, a light source 12 for irradiating light having energy corresponding to a reaction molecule to be treated is provided inside a photochemical reaction tank 11. Further, a supply device 13 for introducing a treatment target such as soil or incinerated ash into the photochemical reaction tank 11 is provided, and a catalyst supply device 14 for supplying a catalyst as needed is provided. In addition, a discharge device 15 is provided for discharging the detoxified solids and produced substances from the photochemical reaction tank 11 by decomposing harmful substances.
[0048]
When natural light is used for the light source 12, the exterior of the photochemical reaction tank 11 may be formed of a member through which natural light passes, or may be configured to be able to be introduced into the reaction tank by condensing or collecting natural light. preferable. In addition, a catalyst may be present on the inner surface of the reaction tank in contact with the reaction molecules in order to promote the reaction.
[0049]
The soil or the like introduced into the photochemical reaction tank 11 from the supply device 13 is irradiated with light having energy to excite the molecules to be decomposed in the photochemical reaction tank 11. At this time, it is preferable to stir the soil or the like and sufficiently irradiate the light. Further, a predetermined catalyst can be supplied from the catalyst supply device 14 as needed. The reaction can be promoted by replenishing the catalyst. Further, it is preferable to heat the photochemical reaction tank 11. The reaction can be promoted by heating. Further, it is preferable to introduce oxygen into the photochemical reaction tank 11. By introducing oxygen, an oxidation reaction and a decomposition reaction can be promoted.
[0050]
Then, the harmful substances are decomposed by performing the treatment for a predetermined time. Soil or the like detoxified by decomposing harmful substances is discharged from the photochemical reaction tank 11 by the discharge device 15.
[0051]
[Action]
Here, a mechanism considered as a reaction mechanism of the present invention will be described with reference to FIG.
In a normal chemical reaction (indicated by a dotted line in FIG. 2), activation energy of E1 is required for a reaction molecule to cross a barrier and become a product molecule. That is, the reaction does not proceed unless the energy corresponding to E1 is supplied, so that the reaction speed is slow and high energy is required to promote the reaction.
[0052]
On the other hand, in the photochemical reaction (shown by a solid line in FIG. 2) according to the present invention, the reaction molecule is excited by irradiating light having energy enough to excite the reaction molecule. Can increase the reactivity. Further, the activation barrier can be reduced by causing a catalyst to act on the reactive molecule in the excited state. That is, a new reaction path having an activation energy of E2 smaller than that of E1 is formed. As described above, the activation barrier is smaller than that of a normal chemical reaction, so that the reaction can easily proceed, and the efficiency of the reaction is high and energy is saved.
[0053]
【Example】
Next, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.
[0054]
Blue dye No. 1 (manufactured by Tokyo Chemical Industry Co., Ltd .; model number F-0147) excited by light having a wavelength of about 630 nm as a reactive molecule, and anthracene (manufactured by Wako Pure Chemical Industries, Ltd .; model number: F-0147) excited by light having a wavelength of about 400 nm 011-09855), using 2,4,5-trichlorophenol (manufactured by Wako Pure Chemical Industries, Ltd .; model number 500-34441) excited by light having a wavelength of about 350 nm, and is excited by light having a wavelength of about 200 nm or less as a catalyst. Using silicon oxide (manufactured by Fuji Silysia Chemical Ltd .; model number CARiACT-Q30) and zirconium oxide (manufactured by Daiichi Rare Element Chemical Co., Ltd .; model number RC100) excited by light having a wavelength of about 250 nm or less. Black light with a wavelength of 300 to 400 nm and an output of 15 W (manufactured by Nippon Electric Co., Ltd .; model number FL15BLB) It was used. The light from the black light used as the light source has sufficient energy to excite the reactive molecules, but has insufficient energy to excite the catalyst.
[0055]
Example 1
A blue dye aqueous solution was prepared by dissolving 0.5 g of the blue dye No. 1 in 1000 ml of distilled water. A predetermined amount of this blue dye aqueous solution was dropped on 10 g of silicon oxide using a hole pipette, and the mixture was sufficiently stirred to prepare a sample. The sample was sufficiently irradiated with light 1 cm below the black light prepared in a dark room. It was left to stand. After irradiation with light for 24 hours, the decomposition rate of the first blue dye was evaluated by quantitative analysis using GC-MS. The results are shown in Table 1.
[0056]
Comparative Example 1
The same operation as in Example 1 was performed except that the light irradiation was not performed.
[0057]
Example 2
The procedure was performed in the same manner as in Example 1 except that zirconium oxide was used instead of silicon oxide as a catalyst.
[0058]
Comparative Example 2
The same operation as in Example 2 was performed, except that the light irradiation was not performed.
[0059]
Comparative Example 3
The same operation as in Example 1 was performed except that silicon oxide was not used.
[0060]
Comparative Example 4
The same operation as in Example 1 was performed except that the light irradiation was not performed and that silicon oxide was not used.
[0061]
Example 3
Anthracene was dissolved in an acetone-water mixed solution to a concentration of 100 ppm to prepare an anthracene-acetone water mixed solution. A fixed amount of this anthracene / acetone water mixed solution was dropped on 10 g of zirconium oxide using a hole pipette, and the mixture was sufficiently stirred to prepare a sample. This sample was sufficiently placed 1 cm below the black light prepared in a dark room. It was left still so that light was irradiated. After irradiation with light for 24 hours, the anthracene decomposition rate was evaluated by quantitative analysis using GC-MS. The results are shown in Table 1.
[0062]
Comparative Example 5
The same operation as in Example 3 was performed except that the light irradiation was not performed.
[0063]
Comparative Example 6
The same operation as in Example 3 was performed except that zirconium oxide was not used.
[0064]
Comparative Example 7
Example 3 was carried out in the same manner as in Example 3, except that light irradiation was not performed and zirconium oxide was not used.
[0065]
Example 4
2,4,5-Trichlorophenol was dissolved in an acetone-water mixed solution to a concentration of 100 ppm to prepare a 2,4,5-trichlorophenol-acetone-water mixed solution. After a predetermined amount of this 2,4,5-trichlorophenol / acetone water mixed solution was dropped on 10 g of zirconium oxide using a hole pipette, a sample was prepared by sufficiently stirring the sample, and the sample was prepared in a black light prepared in a dark room. 1 cm directly below the sample was allowed to stand so that light was sufficiently irradiated. After irradiating with light for 24 hours, the decomposition rate of 2,4,5-trichlorophenol was evaluated by quantitative analysis using GC-MS. The results are shown in Table 1.
[0066]
Comparative Example 8
The same operation as in Example 4 was performed except that the light irradiation was not performed.
[0067]
Comparative Example 9
The procedure was performed in the same manner as in Example 4 except that zirconium oxide was not used.
[0068]
Comparative Example 10
Example 4 was carried out in the same manner as in Example 4 except that light irradiation was not performed and zirconium oxide was not used.
[0069]
[Table 1]

[0070]
From Example 1, Example 2, Example 3 and Example 4, it can be seen that the decomposition reaction is progressing by performing the light irradiation and the presence of the catalyst.
From Comparative Example 1, Comparative Example 2, Comparative Example 5, and Comparative Example 8, it can be seen that the reaction did not proceed when light irradiation was not performed even if a catalyst was present.
From Comparative Example 3, Comparative Example 6, and Comparative Example 9, it can be seen that the reaction did not proceed when the catalyst was not present even after light irradiation.
Comparative Examples 4, 7 and 10 show that the reaction did not proceed when no catalyst was present and no light irradiation was performed.
[0071]
From the above results, it was found that the reaction can proceed with high efficiency by irradiating light having energy to excite the reactive molecule and causing the catalyst to act. That is, without using light having energy enough to directly photodecompose the reaction molecules or energy enough to excite the catalyst, the reaction molecules are irradiated with light having a relatively low energy in the absorption wavelength region of the reaction molecules. The reaction can be allowed to proceed by causing the catalyst to act on the excited reaction molecule without being excited and without photoexciting the catalyst as in the case of a photocatalyst. Thus, a highly efficient chemical reaction can be realized at low cost.
[0072]
【The invention's effect】
As described above, the reactivity of a reactive molecule can be increased by irradiating the reactive molecule with light to excite it, and the activation barrier can be reduced by causing a catalyst to act on the excited reactive molecule. Therefore, the reaction can proceed with low energy, and for example, harmful substances such as dioxins can be efficiently decomposed at low cost.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram for explaining a photochemical reaction apparatus.
FIG. 2 is a drawing for explaining a photochemical reaction.
[Explanation of symbols]
10 Photochemical reaction device
11 Photochemical reaction tank
12 light source
13 Supply device
14 Catalyst supply device
15 Discharge device

Claims (7)

A photochemical reaction method comprising irradiating light having energy to excite a reactive molecule to photoexcit the reactive molecule in a solid phase, and causing a catalyst to act on the excited reactive molecule to cause a reaction. 2. The photochemical reaction method according to claim 1, wherein the reactive molecule is an organic halogen compound. 3. The photochemical reaction method according to claim 1, wherein the reactive molecule is contained in soil or incineration ash. The photochemical reaction method according to any one of claims 1 to 3, wherein the catalyst is a metal oxide. The photochemical reaction method according to any one of claims 1 to 3, wherein the catalyst is a soil component. A method for treating soil or incinerated ash, comprising treating soil or incinerated ash using the photochemical reaction method according to any one of claims 1 to 5. A light source for photo-exciting the reaction molecules is provided in the reaction vessel, and the reaction molecules contained in the soil or incineration ash are irradiated by irradiating light to excite the reaction molecules. An apparatus for treating soil or incinerated ash, characterized in that the apparatus is configured to cause the incineration ash.

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