JP2005254194A - Environmental cleanup microreacter system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a very safe and small environmental cleanup microreactor system capable of reducing ethylene oxide (EO) to 1 ppm or less, discharged from an EO-using sterilizer of a hospital or the like with a high performance and low cost. <P>SOLUTION: This system is provided with an air heating part 1 sucking air of the outside of an apparatus, heating it by a heater and sending at a constant flow rate; a gas mixing chamber 2 mixing toxic gas introduced from the outside of the apparatus with air sent from the heating part 1; and a catalytic reaction part 3 containing a three-dimensionally structured catalyst 32 having numerous fine passages structure with diameters of several to several hundred μm in a reactor 31, in which the mixed gas mixed in the mixing chamber 2 makes to contact with the catalyst while flowing and moving in the catalyst 32, to treat the toxic gas. The catalyst 32 has numerous fine passages (microchannels) with diameters of several to several hundred μm three-dimensionally crossing, joining or branching. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an environmental purification microreactor system for detoxifying harmful gas discharged from a hospital or factory by using a microreactor.

  Ethylene oxide (ethylene oxide) listed as one of the harmful air pollutants (priority action substances) in the “Act on Amending Part of the Air Pollutant Law” promulgated on May 9, 1996 ) Is known to have carcinogenic and harmful effects on the human body, and since this substance is often used for sterilization of hospitals and industrial equipment and industrial intermediates, occupational safety and health It is also regulated by law. And, according to the revised Industrial Safety and Health Law (Enforcement Ordinance Article 21), in an indoor workplace where sterilization work is performed in hospitals and factories, the working environment shall be measured once every six months from September 1, 2002. And the management concentration in Article 2 (Evaluation of measurement results) of the work environment evaluation standard is 1 ppm.

  The sterilization gas that has been used in hospital or industrial sterilizers so far is a mixture of 10 to 30% (100,000 ppm to 300,000 ppm) ethylene oxide and 90 to 70% carbon dioxide gas. Gas or 100% (1 million ppm) ethylene oxide gas is common, and in the case of a sterilizer that is not equipped with an ethylene oxide treatment device, after a sterilization treatment, aeration is repeated several tens of times. The current situation is local disposal or discharge from the vent. For this reason, the concentration of discharged ethylene oxide gas varies depending on the installation location, and the number of times of aeration purification varies depending on the judgment of the user, and the ethylene oxide gas has a considerably high concentration unless a considerable number of aerations are performed. Gas is exhausted, which has a very bad influence on the surrounding environment. Generally, the local waste sterilizer currently discharges ethylene oxide having a concentration of several hundred ppm to several thousand ppm from the ducts, pipes, and exhaust ports into the atmosphere.

  Despite the current situation, there are few ethylene oxide treatment equipment currently on the market that can clear the management standard value of 1 ppm, and the whole equipment is very large and is a commercial refrigerator. Because of its size, there is a problem in terms of installation location, and the device itself is expensive (generally 5 million yen or more), maintenance costs and running costs are high, and it is a heavy burden for hospitals and companies. There are also problems. In addition, the ethylene oxide treatment technology of industrial sterilizers uses a large amount of ethylene oxide, so continuous combustion treatment is carried out for 2 days. However, it requires enormous costs for running costs, and it imposes a high burden on companies. It has been.

  In the future, the regulations on outdoor emission standards (related to ISO 1400) are expected to become stronger, so it is considered important to develop high-performance, low-cost, compact equipment that clears it. It will also have an impact. Furthermore, since ethylene oxide is not only harmful, but its explosion limit is as large as 3 to 100%, it is desired to develop a device that can be safely processed.

  Examples of the ethylene oxide gas treatment apparatus recently proposed include those described in Patent Documents 1 to 3.

  The apparatus of the invention described in the above-mentioned Patent Document 1 repeats the work of discharging ethylene oxide gas remaining in the sterilization tank after sterilization and introducing air into the sterilization tank a plurality of times. An exhaust gas treatment tank is provided on the exhaust side of the exhaust gas, and a reflux path for refluxing the exhaust gas from the treatment tank to the sterilization tank is provided, and the treatment tank has a structure filled with activated carbon or water as an adsorbent. However, in the case of treatment using adsorption with an adsorbent or contact with water, the treatment takes time, and the ethylene oxide gas may be returned to the sterilization tank without being treated. It is difficult to reduce the size.

  The device described in Patent Document 2 is a water-sealed vacuum pump for sending ethylene oxide gas from a sterilization chamber together with water, heat treatment by incorporating ethylene oxide from a sterilization chamber, and activated carbon treatment. The apparatus includes a main body of a discharge processing apparatus for performing a cooling process. This apparatus also has a problem that it takes a long time to process and it is difficult to reduce the size of the apparatus.

  Further, Patent Document 3 discloses an ethylene oxide gas treatment device that introduces ethylene oxide gas into a water tank and discharges it as glycerin. However, this device is also discharged from a general sterilization device. A large water tank is required to process the amount of ethylene oxide gas.

  Thus, none of the ethylene oxide gas treatment apparatuses proposed so far has a structure suitable for downsizing, and when these apparatuses are used, the Industrial Safety and Health Act is It is difficult to achieve the target ethylene oxide emission standard (emission concentration of 1 ppm or less).

  From such a point of view, the present inventors have found that ethylene oxide gas that can be detoxified with high performance (emission concentration of 1 ppm or less), ultra-compact, low price, safe, can be reduced to a concentration that is harmless to the human body. We have been researching and developing mass production prototypes of processing equipment.

JP 2000-312709 A

JP 2000-325751 A JP 2001-205032 A

  The object of the present invention is to solve the above-mentioned problems in the prior art and to have high performance, ultra-small size, low price, extremely low ethylene oxide discharged from sterilizers using ethylene oxide in hospitals and industries, etc. It is an object of the present invention to provide an environment purification microreactor system suitable for a safe ethylene oxide treatment apparatus and other detoxification treatment of harmful gases.

  As a result of various investigations, the present inventors have mixed ethylene oxide gas with heated air, and then three-dimensionally crossed, joined, or branched three-dimensionally of the three-dimensional structure catalyst on which the catalyst is supported. As a result of passing through a large number of micro flow channels (micro channels) having a diameter of μm, it was found that ethylene oxide gas can be detoxified with great efficiency and the above problems can be solved, thereby completing the present invention. In addition, such a microreactor system includes various harmful gases other than ethylene oxide, that is, acrylonitrile, acetaldehyde, vinyl chloride monomer, chloroform, chloromethyl methyl ether, 1,2-dichloroethane, dichloromethane, dioxins, tetrachloroethylene, trichloroethylene, It has been found that it is also effective for detoxification treatment of 1,3-butadiene, benzene, benzo [a] pyrene, formaldehyde and the like, and can be applied as an environmental purification microreactor system.

  That is, the environmental purification microreactor system of the present invention includes an air heating unit capable of inhaling air outside the apparatus, heating the air with a heater, and sending the air at a constant flow rate, the harmful gas introduced from the outside of the apparatus, A gas mixing chamber in which heated air sent from the air heating unit flows in and mixes, and a three-dimensional structure catalyst having a number of microchannel structures with a diameter of several μm to several hundred μm are accommodated in the reactor. A catalytic reaction section in which the harmful gas is rendered harmless by contacting the catalyst while the mixed gas mixed in the gas mixing chamber moves while flowing in the three-dimensional structure catalyst. The three-dimensional structure catalyst comprises a plurality of microchannels having a diameter of several μm to several hundreds of μm that intersect, merge or branch three-dimensionally, and the three-dimensional structure The body catalyst includes Catalyst for detoxifying noxious gas passing through the narrow flow paths are those having features that are supported.

In this case, the three-dimensional structure catalyst is formed by laminating a metal thin plate having a large number of fine holes and a spacer made of a thin dimple-processed wire mesh or a flat thin metal mesh that is not dimple-processed. The harmful gas can be passed through a roll-shaped three-dimensional structure catalyst. In this case, a cut and raised piece can be attached to each fine hole.
The three-dimensional structure catalyst is formed by alternately laminating a plurality of thin flat woven wire meshes and joining them together and spacers made of dimple-processed thin wire meshes or flat thin wire meshes that are not dimple-processed. It can also be arranged in a shape. Further, the three-dimensional structure catalyst includes a plurality of thin metal plates having a large number of fine holes arranged in parallel and spaced apart from each other in a direction substantially perpendicular to the flow direction of the mixed gas. It can be made up of.

  According to the environmental purification microreactor system having the above-described configuration of the present invention, a harmful gas such as ethylene oxide is mixed with heated air, and this mixed gas is several μm that crosses, merges, or branches three-dimensionally in the three-dimensional structure catalyst. By passing through a large number of micro flow channels (micro channels) with a diameter of several hundred μm, the catalytic reaction can be made remarkably efficient, and high-concentration harmful gases can be reduced to 1 ppm in a few seconds. In addition, it is possible to provide a very safe environment-purifying microreactor system that can be downsized to about 1/10 of the conventional apparatus, is inexpensive, and is extremely safe. It can be easily mounted on existing sterilizers by taking advantage of its ultra-small features.

  As a three-dimensional structure catalyst, a three-dimensional structure is formed by winding a thin metal plate having a large number of fine holes and a spacer made of a thin dimple-processed wire mesh or a flat thin wire mesh not dimple-processed into a roll shape. A microreactor having a large number of microchannels with a diameter of several μm to several hundreds of μm that originally intersect, merge, or branch can be easily manufactured, enabling mass production. In addition, as a three-dimensional structure catalyst, a plurality of thin flat woven wire meshes are joined and integrated together, and a dimple-processed thin wire mesh or a spacer made of a flat thin wire mesh that is not dimple-processed is alternately laminated. Also, by arranging them in a simple manner, it is possible to facilitate the processing and mass production of a microreactor having a large number of micro flow channels with a diameter of several μm to several hundred μm.

  A preferred embodiment when the environmental purification microreactor system of the present invention is applied to an ethylene oxide gas processing apparatus will be described with reference to the drawings, but the present invention is not limited to this.

  FIG. 1 is a system diagram of a preferred example of the environmental purification microreactor system of the present invention. 2 is a system diagram of another example, FIG. 3 is a partially enlarged perspective view of a spacer 6 which is one of the components of the three-dimensional structure catalyst, and FIG. 4 is a longitudinal front view of a partly enlarged view of the three-dimensional structure catalyst. FIG. 5 is a partially enlarged cross-sectional plan view of the three-dimensional structure catalyst.

  In FIG. 1, the environmental purification microreactor system includes an air heating unit 1, a gas mixing chamber 2, and a catalyst reaction unit 3.

  In the air heating unit 1, air (room temperature) outside the apparatus is sucked from the suction port 1 a and is heated by the internal heater 1 c while passing through the inside, and is sent out from the discharge port 1 b at a constant flow rate. In this case, in order to send heated air at a constant flow rate, it is common to adjust the air before preheating with a flow meter (not shown).

  In the illustrated example, the air outside the apparatus is sucked from the lower side of the apparatus, but is not limited to such a structure. Moreover, the heater 1c can also be provided in the inner peripheral wall surface of the air heating part 1, or an outer peripheral wall surface.

  In the air heating unit 1, generally, air sucked at room temperature is heated at a heater temperature of 190 to 210 ° C., and is heated to about 70 to 200 ° C. and sent to the gas mixing chamber 2. The air heating unit 1 preferably has a stable temperature characteristic in which a predetermined temperature can be quickly obtained, subtle temperature control is possible, and hot hot air can be generated continuously for a long time. It is preferable that the thermal conductivity transmitted to the air is high, for example, designed to be 80% or more.

  The heated air from the air heating unit 1 is sent to the gas mixing chamber 2, and harmful gases such as ethylene oxide discharged from the sterilizer are also introduced into the gas mixing chamber 2. Done. In the apparatus of the present invention, preheated air and harmful gas are mixed when the harmful gas to be detoxified is ethylene oxide gas, and the explosion limit of ethylene oxide is as wide as 3% to 100%. This is to prevent explosion when heated to a concentration of ethylene oxide.

  In the present invention, the mixing ratio of the harmful gas introduced from the outside of the apparatus and the heated air sent from the air heating unit 1 (each gas inflow amount per unit time) can be appropriately selected. When the harmful gas is an ethylene oxide gas, it is generally preferable that the ethylene oxide concentration of the mixed gas is about 0.3% (3,000 ppm) to about 3% (30,000 ppm). .

  As shown in FIG. 1, the catalyst reaction unit 3 contains a three-dimensional structure catalyst 32 on which a catalyst is supported in a reactor 31, and the mixed gas mixed in the gas mixing chamber 2 is three-dimensional. This is the part where the harmful gas detoxification process is achieved by contacting the catalyst while moving in the structure catalyst 32 while flowing. The three-dimensional structure catalyst 32 has innumerable fine channels (microchannels) having a diameter of several μm to several hundred μm that intersect, merge or branch three-dimensionally. A catalyst for detoxifying harmful gas passing through the fine flow path is supported.

  In addition, the catalyst reaction part 3 of the other example shown in FIG. 2 forms the three-dimensional structure catalyst 32 in a plate shape, and a heat exchange unit 33 formed in the same plate shape as the three-dimensional structure catalyst 32, It is configured by alternately laminating. Although not shown, for example, a catalyst is coated on the surface of the fin of a so-called “cross fin heat exchanger” in which a heat transfer tube is disposed through a large number of plate fins, and this is used as a three-dimensional structure catalyst 32. The catalyst reaction part 3 can also be comprised.

  Further, FIG. 1 shows a structural example provided with one reactor 31, but the number of reactors 31 can be arbitrarily increased or decreased according to the conditions such as the amount of processing gas. For example, either a serial arrangement or a parallel arrangement can be adopted. Moreover, in FIG. 1, the code | symbol 3a is a gas inlet part and 3b is a gas exhaust port.

  As shown in FIGS. 4 and 5, the three-dimensional structure catalyst 32 is made of a metal such as stainless steel having a large number of fine holes (square holes) 4a and cut and raised pieces 4b that are cut and raised when the fine holes 4a are punched. The thin plate 4 and a spacer 6 (see FIG. 3) formed by dimple processing a thin plain woven wire mesh 5 are overlapped and wound in a roll shape to the center. The roll-shaped three-dimensional structure catalyst 32 is accommodated in the reactor 31 so that the central axis thereof coincides with the central axis of the reactor 31 (see FIG. 2). For example, the aperture ratio of the thin metal plate 4 is 30 to 70%, the plate thickness is 10 to 500 μm (preferably about 50 μm), and the hole diameter of the fine holes 4a is 30 to 500 μm. The plain weave wire mesh 5 is composed of a vertical line 5a and a horizontal line 5b made of stainless steel wire or the like, and intersecting each other at regular intervals, and the mesh (number of meshes included in 25.4 mm square) is 10 to 100. It is. Depending on the fine holes 4a of the metal thin plate 4, the gap between the metal thin plate 4 and the plain weave wire mesh 5, and the mesh of the plain weave wire mesh 5, a fine flow path having a diameter of several μm to several hundred μm, preferably not more than 500 μm, more preferably about 100 to 300 μm. It is formed so that there are about 1 to 2 million (microchannels). The spacer 6 may be made of a flat plain woven wire mesh 5 that is not dimple processed, or may be a wire mesh other than the plain woven wire mesh 5. In FIG. 4, arrow 10 indicates the gas inflow side, and arrow 11 indicates the gas outflow side.

  Catalysts supported on the three-dimensional structure catalyst 32 include aluminum oxide, silicon dioxide, titania (titanium oxide), aluminum oxide supporting platinum, silicon dioxide supporting nickel, cerium oxide, and platinum. The three-dimensional structure catalyst 32 is used and coated with a wash coat, electrodeposition or the like to a thickness of about 10 to 100 μm.

  In the three-dimensional structure catalyst 32, since there are about 100 million fine holes 4a having a hole diameter of 30 to 100 μm in one metal thin plate 4, the flow of the mixed gas becomes a laminar flow. Since the movement time of mass transfer and heat transfer is proportional to the square of the microchannel diameter, it takes a very short time in the microchannel (diffusion time 1 / 10,000, specific surface area 100 times). As a result, the concentration and temperature of the mixed gas in the microchannel become uniform, the oxygen concentration in the vicinity of the surface of the metal thin plate 4 is always kept high, and the effect of the through-holes serving as inlets and outlets is combined with the effect of microchanneling. A highly efficient catalytic reaction can be performed by a synergistic effect of a very large surface area and a complicated flow such as crossing, merging, and branching.

  Such a microreactor composed of the three-dimensional structure catalyst 32 has a larger space velocity (SV) than a conventional ceramic or activated carbon granular carrier or honeycomb carrier, so that the amount of catalytic reaction is increased and the treatment per unit time is increased. The amount is tremendously large.

  As a catalyst, in particular, a catalyst in which platinum is supported on aluminum oxide or a catalyst in which nickel, cerium oxide, and platinum are supported on silicon dioxide reduces high-concentration ethylene oxide (3,000 ppm) to 1 ppm in several tens of milliseconds. In addition, the reaction can be performed at a low temperature of about 200 ° C.

  In the metal thin plate 4 having a large number of fine holes (square holes) 4a, the cut and raised pieces 4b attached to the respective fine holes 4a exert an effect of increasing the surface area of the catalyst and promoting the mixing of the mixed gas as a micromixer. The spacer 6 made of the plain woven wire mesh 5 exhibits not only the function of maintaining the distance between the layers of the thin metal plate 4 and the formation of a fine flow path, but also exhibits the effect of promoting the mixing of the mixed gas as a micromixer. In particular, as shown in FIG. The spacer 6 made of the processed plain woven wire mesh 5 can impart elasticity to the three-dimensional structure catalyst 32.

  In addition, as the three-dimensional structure catalyst 32, a plurality of thin flat woven wire meshes 7 as shown in FIG. 6 (two in FIG. 7) are stacked and joined and integrated by sintering or the like (see FIG. 6). 7) and spacers 6 similar to the spacers 6 made of the thin plain woven wire mesh 5 that has been dimple processed or the flat thin woven wire mesh 5 that has not been dimple processed (see FIG. 8). reference).

  As shown in FIG. 6, the flat woven wire mesh 7 is woven by enlarging the mesh by the vertical lines 7a made of stainless steel wires and the like, and the horizontal lines 7b are in close contact with each other. There is no “open mesh”, and the mixed gas passes through a gap in the order of μm at the intersection of the vertical line 7a and the horizontal line 7b. The mesh of the flat woven wire mesh 7 (number of vertical lines × number of horizontal lines in 25.4 mm square) is, for example, 12 × 64. As shown in FIG. 7, when two flat woven wire meshes 7 are stacked and joined and integrated by sintering or the like, the upper flat woven wire mesh 7 and the lower flat woven wire mesh 7 are oriented vertically and horizontally 90. In other words, the metal meshes 7 and 7 are made dense with each other by overlapping each other so that the vertical lines 7a of the lower flat woven wire mesh 7 are orthogonal to the vertical lines 7a of the upper flat woven wire mesh 7. They are overlaid so that an appropriate gap is formed between the polymerization surfaces without sticking to each other. Depending on the mesh of the plain woven wire mesh 7, the gap between the plain woven wire meshes 7, 7, the gap between the plain woven wire mesh 7 and the plain woven wire mesh 5, and the mesh of the plain woven wire mesh 5, the diameter is several μm to several hundred μm. Innumerable fine channels (microchannels) are formed. In FIG. 8, arrow 10 indicates the gas inflow side, and arrow 11 indicates the gas outflow side.

  Further, as the three-dimensional structure catalyst 32, as shown in FIG. 9, a metal thin plate 9 such as stainless steel in which a large number of slit-like fine holes (width of about 400 μm) 9a are arranged at predetermined intervals (about 400 μm) is manufactured. In addition, the metal thin plate 9 and the spacer 6 similar to the spacer 6 made of the thin plain woven wire mesh 5 dimpled or the flat thin plain woven wire mesh 5 not dimpled may be alternately arranged in a laminated form. . In this case, the plurality of thin metal plates 9 are stacked in a vertical direction so that the slit-like fine holes 9a of the lower metal thin plate 9 are perpendicular to the slit-like fine holes 9a of the upper metal thin plate 9. The

  The microreactor of the above embodiment can have a large number of microchannels with a diameter of several μm to several hundred μm, and can be downsized to about 1/10 the size of a conventional apparatus while having the above performance. be able to. Further, a current can be directly applied to the three-dimensional structure catalyst 32 and used as a heater. Moreover, since the catalyst is directly supported on the three-dimensional structure catalyst 32, the temperature distribution is uniform and the reaction efficiency is remarkably increased. By supporting the catalyst on the three-dimensional structure catalyst 32, the heat generated by the reaction can be used and preheated, so that the processing gas can have a function as a heat exchanger.

  The environmental purification microreactor system comprising the microreactor having the above-described features is ultra-compact and can be reduced in cost, and the running cost can be greatly reduced.

  The environmental purification microreactor system of the present invention is not only for the treatment of ethylene oxide, but among the priority substances specified by Japan, acrylonitrile, acetaldehyde, vinyl chloride monomer, chloroform, chloromethyl methyl ether, 1,2-dichloroethane, Since dichloromethane, dioxins, tetrachloroethylene, trichloroethylene, 1.3-butadiene, benzene, benzo [a] pyrene, and formaldehyde can provide the same performance as in the case of ethylene oxide treatment, the above substances can be applied.

Catalyst Combustion Experiment Using 3% Ethylene Oxide Gas The catalytic reaction section 3 has a large number of fine holes (square holes) 4a as shown in FIGS. 4 and 5, and a cut and raised piece 4b is provided in each fine hole 4a. A thin metal plate 4 such as stainless steel and a spacer 6 formed by dimple processing a thin plain woven wire mesh 5 are overlapped and wound in a roll shape to the center, and this is coated with an aluminum oxide catalyst to a thickness of about 100 μm by wash coating. A three-dimensional structure catalyst 32 was prepared and stored in a reactor 31 having an inner diameter of 17 cm and a vertical length of 10 cm so that the central axis X of the three-dimensional structure catalyst 32 was in the vertical and vertical directions. As the air heating unit, a commercially available hot air generator (manufactured by Infridge Industrial Co., Ltd., model number: SEN-100V-1000W-AS) is used, and the environment purification microreactor system of the present invention having the structure shown in FIG. The air outside the apparatus can be sucked and heated to about 200 ° C., the amount of heated air introduced from the air heating unit to the gas mixing chamber is 10 liters / minute, and 3% ethylene oxide gas (EO) ) Was introduced at 20 liters / minute, the flow rate was increased based on this concentration ratio, and the performance limit of the catalyst was investigated.

  In the above test, a sample was collected in a Tedlar bag from the gas outlet 3c shown in FIG. 1 and then measured with a gas chromatograph (GC).

(Gas chromatograph)
Measurement value: gas chromatograph (GC-6A: manufactured by Shimadzu Corporation)
Detector: FID
Column: Flexol 8N8
Column temperature: 50 ° C
The results of the above experiment are as shown in FIG. Reaction gases (carbon dioxide diluted ethylene oxide 10000 ppm 70 l / min and air 100 l / min) were introduced into a microreactor packed with 1 wt% pt / Al ₂ O _{3 /} SUS structure catalyst. At a reaction temperature of 250 ° C. or higher, the reaction rate reached almost 100% and could not be detected in the effluent gas by a gas chromatograph (FID). The product was only water and carbon dioxide, and no other by-products were produced.

  As can be seen from the above experimental results, the catalyst reaction part is equipped with a microreactor having a large number of microchannels with a diameter of several μm to several hundreds of μm that intersect, merge or branch in three dimensions. In addition, the environmental purification microreactor system of the present invention is very effective for the treatment of ethylene oxide gas, can meet strict environmental standards, and the adoption of the microreactor can make the apparatus very small and compact.

  A high performance, extremely safe and ultra-small environmental purification microreactor system can be provided at a low price for the detoxification of harmful gases such as ethylene oxide, acrylonitrile and acetaldehyde.

1 is a system diagram showing a preferred embodiment of an environmental purification microreactor system of the present invention. It is a system diagram which shows the other example of an environmental purification microreactor system. It is a perspective view which shows the dimple processing state of the spacer which consists of metal meshes. It is a longitudinal front view of a partial enlargement of the three-dimensional structure catalyst. It is a cross-sectional plan view of a partially enlarged three-dimensional structure catalyst. 6A is a plan view, FIG. 6B is a cross-sectional view taken along the line AA in FIG. 6A, and FIG. 6C is a cross-sectional view taken along the line BB in FIG. 6A. It is sectional drawing of the wire-mesh laminated body formed by sintering the plain woven wire-mesh of FIG. It is sectional drawing of the three-dimensional structure catalyst of another example. Furthermore, it is a perspective view of the metal thin plate which comprises the three-dimensional structure catalyst of another example. It is sectional drawing of the three-dimensional structure catalyst which consists of a metal thin plate of FIG. It is a graph which shows the temperature dependence of the ethylene oxide catalyst combustion obtained from the experiment of the Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air heating part 2 Gas mixing chamber 3 Catalytic reaction part 4 Metal thin plate 4a Fine hole 4b Cut and raised piece 5 Flat tatami wire mesh 6 Spacer 7 Flat woven wire mesh 8 Wire mesh laminated body 9 Metal thin plate 9a Fine hole 31 Reactor 32 Three-dimensional structure Body catalyst 33 Heat exchange unit

Claims (8)

  Air heating unit that sucks air outside the device, heats the air with a heater and delivers it at a constant flow rate, harmful gas introduced from the outside of the device, and heated air sent from the air heating unit flow in A gas mixing chamber in which mixing is performed, and a three-dimensional structure catalyst having a large number of fine channel structures with a diameter of several μm to several hundred μm are housed in the reactor, and mixed in the gas mixing chamber. A catalytic reaction section in which a detoxification treatment of the harmful gas is achieved by contacting the catalyst while the mixed gas moves while flowing in the three-dimensional structure catalyst, and the three-dimensional structure catalyst comprises: An environmental purification microreactor system comprising a large number of micro flow channels having a diameter of several μm to several hundreds of μm that intersect, merge or branch three-dimensionally.   2. The three-dimensional structure catalyst according to claim 1, wherein the three-dimensional structure catalyst is formed by laminating a metal thin plate having a large number of fine holes and a spacer made of a thin dimple-processed wire mesh or a flat thin metal mesh not dimple-processed. Environmental purification microreactor system.   The environmental purification microreactor system according to claim 2, wherein a cut and raised piece is attached to each fine hole of the metal thin plate.   The three-dimensional structure catalyst is formed by alternately laminating a wire mesh laminate in which a plurality of thin flat woven wire meshes are joined and integrated, and a spacer made of a dimple-processed thin wire mesh or a flat thin wire mesh that is not dimple-processed. The environmental purification microreactor system according to claim 1, which is arranged.   The three-dimensional structure catalyst is formed by arranging a plurality of thin metal plates having a large number of fine holes in parallel with each other in a direction substantially perpendicular to the flow direction of the mixed gas. The environmental purification microreactor system according to claim 1, comprising:   The harmful gas is ethylene oxide, acrylonitrile, acetaldehyde, vinyl chloride monomer, chloroform, chloromethyl methyl ether, 1,2-dichloroethane, dichloromethane, dioxins, tetrachloroethylene, trichloroethylene, 1.3-butadiene, benzene, benzo [a]. The environmental purification microreactor system according to any one of claims 1 to 5, which is selected from the group consisting of pyrene and formaldehyde.   The environmental purification microreactor system according to any one of claims 1 to 6, wherein the catalyst is one in which platinum is supported on aluminum oxide.   The environmental purification microreactor system according to any one of claims 1 to 6, wherein the catalyst is a catalyst in which nickel, cerium oxide, and platinum are supported on silicon dioxide.

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