WO2013124998A1 - Appareil de transport de chaleur, et procédé de transport de chaleur - Google Patents

Appareil de transport de chaleur, et procédé de transport de chaleur Download PDF

Info

Publication number
WO2013124998A1
WO2013124998A1 PCT/JP2012/054346 JP2012054346W WO2013124998A1 WO 2013124998 A1 WO2013124998 A1 WO 2013124998A1 JP 2012054346 W JP2012054346 W JP 2012054346W WO 2013124998 A1 WO2013124998 A1 WO 2013124998A1
Authority
WO
WIPO (PCT)
Prior art keywords
nitrous oxide
gas
decomposition
catalyst
heat
Prior art date
Application number
PCT/JP2012/054346
Other languages
English (en)
Japanese (ja)
Inventor
茂広 茶圓
川口　淳一郎
宏人 羽生
理嗣 曽根
Original Assignee
昭和電工株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 昭和電工株式会社 filed Critical 昭和電工株式会社
Priority to PCT/JP2012/054346 priority Critical patent/WO2013124998A1/fr
Publication of WO2013124998A1 publication Critical patent/WO2013124998A1/fr

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/86—Catalytic processes
    • B01D53/8621—Removing nitrogen compounds
    • B01D53/8625—Nitrogen oxides
    • B01D53/8631—Processes characterised by a specific device
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/10—Noble metals or compounds thereof
    • B01D2255/102—Platinum group metals
    • B01D2255/1025—Rhodium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/20—Metals or compounds thereof
    • B01D2255/204—Alkaline earth metals
    • B01D2255/2047—Magnesium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/20—Metals or compounds thereof
    • B01D2255/209—Other metals
    • B01D2255/2092—Aluminium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2255/00—Catalysts
    • B01D2255/40—Mixed oxides
    • B01D2255/405—Spinels
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02C—CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG]
    • Y02C20/00—Capture or disposal of greenhouse gases
    • Y02C20/10—Capture or disposal of greenhouse gases of nitrous oxide (N2O)

Definitions

  • the present invention relates to a heat transport apparatus and a heat transport method using energy generated by decomposition of nitrous oxide (also referred to as N 2 O, dinitrogen monoxide).
  • nitrous oxide also referred to as N 2 O, dinitrogen monoxide
  • Japanese Patent Laid-Open No. 5-4027 Japanese Patent Laying-Open No. 2005-230795 JP 2006-181570 A Japanese Patent No. 4232820
  • heating including heating, hot water supply, hot water, drying, etc.
  • cooling including cooling, refrigeration, freezing, cold water, ice making, etc.
  • dehumidification and humidification
  • nitrous oxide as energy friendly to the global environment by using energy generated by decomposition of nitrous oxide.
  • Nitrous oxide is chemically stable and easy to handle, and is approved as a food additive (Ministry of Health, Labor and Welfare No. 34, March 22, 2005). It is also used as a combustion aid.
  • nitrous oxide is considered to be one of the causes of global warming as a greenhouse gas having a warming effect about 310 times that of carbon dioxide (CO 2 ).
  • CO 2 carbon dioxide
  • many technologies have been developed to decompose and remove nitrous oxide in exhaust gas discharged from, for example, factories, incineration facilities, and automobiles using catalysts. (For example, see Patent Documents 1 to 3.)
  • Patent Documents 1 and 2 disclose a technique in which heat generated during decomposition of nitrous oxide in the production process of adipic acid is used for preheating nitrous oxide.
  • Patent Document 3 described above in an apparatus for decomposing nitrous oxide contained in excess anesthetic gas, heat exchange is performed between a gas introduced into the decomposition apparatus and a gas discharged from the decomposition apparatus. Discloses a technique for increasing energy efficiency by reducing heating energy and cooling energy.
  • Patent Document 4 a thruster device that generates thrust by using a cracked gas obtained by catalytically decomposing nitrous oxide.
  • nitrous oxide when nitrous oxide is decomposed using a catalyst for decomposing nitrous oxide, additional nitrous oxide may be self-decomposed (thermal decomposition) by the heat of decomposition. Is possible.
  • the object of the present invention is to enable the use of nitrous oxide as energy friendly to the global environment, and also to provide a heat transport device and heat that enable heat transport using energy generated by decomposition of this nitrous oxide. It is to provide a transportation method.
  • the present invention provides the following means.
  • An endothermic heat exchange section that absorbs heat by heat exchange with the outside while the nitrous oxide gas obtained by adiabatic expansion of nitrous oxide passes through the inside;
  • a nitrous oxide decomposition catalyst that decomposes the nitrous oxide is disposed inside, and the nitrous oxide gas is decomposed by the nitrous oxide decomposition catalyst while the nitrous oxide gas passes through the catalyst.
  • a heat transport device comprising: a heat-dissipating side heat exchanging part that dissipates heat by exchanging heat with the outside while cracked gas obtained by decomposing nitrous oxide gas in the cracking reaction part passes through the inside.
  • the heat transport device according to (4), wherein the concentration adjusting means adjusts the concentration of the nitrous oxide gas by adding nitrogen gas to the nitrous oxide gas.
  • a temperature measuring means for measuring the temperature of the nitrous oxide decomposition catalyst or decomposition gas is provided, The flow rate adjustment by the flow rate adjustment unit or the concentration adjustment by the concentration adjustment unit is performed based on the measurement result by the temperature measurement unit, or any one of the above items (3) to (5), Heat transport equipment.
  • (7) comprising preheating means for preheating the nitrous oxide decomposition catalyst, 7.
  • the heat transport device according to any one of the above items (2) to (6), wherein the nitrous oxide decomposition catalyst is preheated before the decomposition of the nitrous oxide is started.
  • nitrous oxide gas obtained by adiabatic expansion of nitrous oxide an endothermic step that absorbs heat by heat exchange with the outside;
  • a heat transport method comprising: a heat dissipation step of dissipating heat by heat exchange with the outside using a decomposition gas of nitrous oxide obtained by decomposing the nitrous oxide gas.
  • the nitrous oxide gas is supplied to a decomposition reaction section where the nitrous oxide decomposition catalyst is arranged, and the nitrous oxide gas is used in the decomposition reaction section using the nitrous oxide decomposition catalyst.
  • nitrous oxide As described above, according to the present invention, it is possible to use nitrous oxide as energy friendly to the global environment, and it is possible to transport heat using the energy generated by the decomposition of nitrous oxide.
  • a heat transport apparatus and a heat transport method to which the present invention is applied use substituting energy generated by the decomposition of nitrous oxide (N 2 O, also referred to as dinitrogen monoxide) as sub-environment-friendly energy.
  • Nitrogen oxide can be used.
  • Nitrous oxide is a stable gas at normal temperature and atmospheric pressure.
  • the temperature is about 500 ° C. or higher, self-decomposition (thermal decomposition) occurs while generating heat.
  • decomposition of nitrous oxide is accompanied by exotherm (exothermic reaction).
  • the decomposition gas of the nitrous oxide heated up by the temperature rise (heat of decomposition) accompanying this decomposition becomes about 1600 degreeC, it can be said that nitrous oxide is a substance with built-in high energy.
  • the decomposition start temperature can be lowered to, for example, about 350 to 400 ° C.
  • disassembly of nitrous oxide it is possible to carry out decomposition
  • the nitrous oxide decomposed using the catalyst becomes a mixed gas (decomposed gas) of nitrogen (N 2 ) and oxygen (O 2 ) while generating heat.
  • FIG. 1 is a schematic diagram for explaining a heat transport apparatus and a heat transport method to which the present invention is applied.
  • the present invention performs heat transport using the energy generated by the decomposition of nitrous oxide.
  • the present invention relates to cooling heat (low temperature) accompanying adiabatic expansion of nitrous oxide,
  • cooling heat low temperature
  • high temperature high temperature
  • the present invention uses nitrous oxide itself as a heat medium (refrigerant / heat medium) for transporting heat.
  • a heat transport device to which the present invention is applied includes a decomposition reaction section 2 in which a nitrous oxide decomposition catalyst (hereinafter simply referred to as a catalyst) 1 that decomposes nitrous oxide is disposed. And a heat absorption side heat exchange part 3 arranged on the upstream side of the decomposition reaction part 2, a heat release side heat exchange part 4 arranged on the rear side of the decomposition reaction part 2, and a high pressure filled with nitrous oxide.
  • a nitrous oxide decomposition catalyst hereinafter simply referred to as a catalyst
  • the first supply line 6 that supplies the nitrous oxide gas (N 2 O) discharged from the high-pressure gas container 5 and adiabatically expanded to the heat absorption side heat exchange unit 3, and the heat absorption side heat exchange unit 3
  • the heat transport method to which the present invention is applied has an endothermic step S1 in which heat is absorbed by heat exchange with the outside using nitrous oxide gas obtained by adiabatic expansion of nitrous oxide.
  • a heat radiation step S3 for heat radiation for heat radiation.
  • nitrous oxide gas is released from the high-pressure gas container 6 and adiabatically expands. Then, the nitrous oxide gas whose temperature has been lowered by the temperature drop (cooling heat) associated with the adiabatic expansion is supplied to the heat absorption side heat exchange unit 3 via the first supply line 6. At this time, the heat absorption side heat exchange unit 3 absorbs heat by heat exchange with the outside while the low-temperature nitrous oxide gas passes through the inside. Thereby, this heat absorption side heat exchange part 3 side can be cooled using the cooling heat accompanying adiabatic expansion of nitrous oxide. Further, by providing the fan (air blowing means) 10 on the heat absorption side heat exchanging portion 3 side, it is possible to efficiently discharge the cold air TL to the outside.
  • nitrous oxide gas is decomposed in the decomposition reaction section 2. Then, the decomposition gas of nitrous oxide that has been heated by the temperature rise (decomposition heat) accompanying this decomposition is supplied to the heat radiation side heat exchange unit 4 through the third supply line 8. At this time, in the heat radiating side heat exchanging unit 4, heat is radiated by heat exchange with the outside while the high-temperature decomposition gas passes through the inside. Thereby, this heat radiation side heat exchange part 4 side can be heated using decomposition heat generated by decomposition of nitrous oxide. Further, by providing a fan (air blowing means) 11 on the radiating side heat exchanging unit 4 side, it is possible to efficiently release the hot air T H to the outside.
  • the cooling heat (low temperature) accompanying the adiabatic expansion of nitrous oxide and the heat of decomposition (high temperature) generated by the decomposition of nitrous oxide are obtained.
  • two levels of temperature range (low temperature and high temperature) from one kind of gas are obtained.
  • nitrous oxide itself, which is an energy source (heat source)
  • heat source heat source
  • the cracked gas can be used as a heat medium.
  • the decomposition reaction unit 2 includes a main body (decomposition reaction chamber) 2a containing the catalyst 1 inside, a gas inlet 2b through which nitrous oxide gas is introduced to one end of the main body 2a, and the main body. It has a structure in which a gas discharge port 2c through which cracked gas is discharged is provided on the other end side of 2a.
  • a material having excellent heat resistance and oxidation resistance for the decomposition reaction portion 2 and in particular, a member on the side of the gas outlet 2 c exposed to high temperature and high pressure by the decomposition gas has a high temperature. It is preferable to use a material that can sufficiently withstand thermal fatigue or oxidation under high pressure. Examples of such materials include stainless steel, Ni-base alloy, and Co-base alloy. Moreover, ceramics, silicon carbide (SiC), or the like can be used as a heat shielding material. Further, these composite materials may be used. Moreover, the decomposition reaction part 2 may be provided with a mechanism forcibly cooling by water cooling or air cooling.
  • the catalyst 1 it is preferable to use a catalyst that can efficiently decompose nitrous oxide in a wide temperature range (especially a low temperature range) and can sufficiently withstand thermal fatigue, oxidation, and the like at high temperatures.
  • a catalyst having high decomposition efficiency of nitrous oxide and excellent heat resistance and oxidation resistance are disclosed in, for example, “JP 2002-153734 A” and “JP 2002-253967 A” described later. Things can be used.
  • any of the catalysts shown in the following [1] to [6] can be used.
  • [1] A catalyst in which aluminum (Al), magnesium (Mg), and rhodium (Rh) are supported on a carrier.
  • [2] A catalyst in which magnesium (Mg) and rhodium (Rh) are supported on an alumina (Al 2 O 3 ) support.
  • [3] A catalyst in which rhodium (Rh) is supported on a carrier in which a spinel crystalline composite oxide is formed of at least a part of aluminum (Al) and magnesium (Mg).
  • At least one metal selected from the group consisting of zinc (Zn), iron (Fe), manganese (Mn) and nickel (Ni), aluminum (Al) and rhodium (Rh) is supported on the carrier.
  • At least one metal selected from the group consisting of zinc (Zn), iron (Fe), manganese (Mn) and nickel (Ni) and rhodium (Rh) are supported on an alumina (Al 2 O 3 ) support. Catalyst.
  • a spinel crystalline composite comprising at least a part of aluminum (Al) and at least one metal selected from the group consisting of zinc (Zn), iron (Fe), manganese (Mn), and nickel (Ni)
  • the support selected from silica (SiO 2 ) and silica alumina (SiO 2 —Al 2 O 3 ) is at least selected from the group consisting of rhodium (Rh), ruthenium (Ru), and palladium (Pd).
  • Rh rhodium
  • Ru ruthenium
  • Pd palladium
  • a catalyst or the like carrying one noble metal can be suitably used.
  • the catalyst 1 is obtained by impregnating a cordierite and metal honeycomb or porous ceramic carrier coated with alumina with a rhodium effective in decomposing nitrogen oxides by 2 to 3% by mass,
  • a support layer made of alumina is formed on a honeycomb structure made of alumina, cordierite, or silicon carbide, and rhodium that is effective in decomposing nitrogen oxides is supported on the support layer.
  • it is not necessarily limited to these.
  • a catalyst used for decomposing and removing nitrous oxide in exhaust gas discharged in a production process of adipic acid, a production process of nitric acid, or the like can be used.
  • Such a catalyst is represented by, for example, MAl 2 O 3 (M is any one of Pd, Cu, Cu / Mg, Cu / Zn, Cu / Zn / Mg), and M is 10 to 30.
  • M is any one of Pd, Cu, Cu / Mg, Cu / Zn, Cu / Zn / Mg
  • M is 10 to 30.
  • Examples thereof include a support in which a precious metal is supported at a rate of 0.1 to 2% by mass on an alumina support containing at a rate of mass%.
  • the shape of the catalyst 1 is not particularly limited.
  • any shape such as powder, granule, pellet, honeycomb, porous, pulverized, mesh, plate, or sheet can be used. What is necessary is just to select and use the optimal shape and size suitably from shapes.
  • the method for filling the main body 2a of the catalyst 1 and the shape of the main body 2a according to the catalyst 1 can be arbitrarily implemented according to the design of the decomposition reaction section 2.
  • the decomposition reaction unit 2 may be configured to be able to replace the catalyst 1 (in some cases, the main body 2a) in accordance with the deterioration of the catalyst 1 with time.
  • a heater (preheating means) 13 for heating the catalyst 1 is provided in the decomposition reaction section 2.
  • the heater 13 preliminarily moves the catalyst 1 to a temperature at which the nitrous oxide gas can be decomposed (decomposition start temperature) before starting the decomposition of nitrous oxide, that is, before supplying the nitrous oxide gas to the decomposition reaction unit 2. It is for heating (preheating).
  • the heater 13 shown in FIG. 1 is disposed inside the main body portion 2a in contact with the periphery of the catalyst 1.
  • the heater 13 is connected to a power source (not shown) via a power supply line 14 and can generate heat by supplying power from the power source.
  • a resistance heating method, an induction heating method, or the like can be used as the heater 13, as the heater 13, a resistance heating method, an induction heating method, or the like.
  • the heating method of the catalyst 1 is not limited to the method of heating the catalyst 1 with the heater 13 disposed inside the main body 2a, and the catalyst 1 is heated with the heater 13 disposed outside the main body 2a. It is also possible to use a method of heating. In this case, the main body 2a can be heated by the heater 13, and the catalyst 1 can be heated by radiation or heat conduction from the main body 2a.
  • a method for heating the catalyst 1 a method of heating the catalyst 1 by directly supplying electric power to the catalyst 1 can be used.
  • the method for heating the catalyst 1 is not particularly limited, and can be appropriately selected from the methods for heating the catalyst 1.
  • the heat absorption side heat exchanging unit 3 is connected to the first supply line 6 on the input side and the second supply line 7 on the output side, and the heat from the outside while the nitrous oxide gas passes through the inside. It is a heat exchanger on the low temperature side that performs exchange.
  • the fin tube type heat exchanger is used for this heat absorption side heat exchange part 3, it is possible to use a heat exchanger of various types and sizes according to the use.
  • the types of heat exchangers include tube type (double pipe type, multi-pipe type (shell & tube type), spiral type, etc.), plate type, regenerative type, etc. These may be selected and used as appropriate according to the application.
  • the heat absorption side heat exchange part 3 can be used as a cooler (cooling means) which cools with the cooling heat accompanying the adiabatic expansion of nitrous oxide.
  • the heat radiation side heat exchanging unit 4 is connected to the third supply line 8 on the inlet side and the discharge line 9 on the outlet side, and performs heat exchange with the outside while the cracked gas passes through the inside. It is a heat exchanger.
  • the fin tube type heat exchanger is used for the heat radiation side heat exchanging section 4, various types and sizes of heat exchangers can be used depending on the application.
  • the types of heat exchangers include tube type (double pipe type, multi-pipe type (shell & tube type), spiral type, etc.), plate type, regenerative type, etc. These may be selected and used as appropriate according to the application.
  • the heat-radiation side heat exchange part 4 can be used as a heater (heating means) which heats with the decomposition heat generated by decomposition of nitrous oxide.
  • the high-pressure gas container 5 is a nitrous oxide gas supply source that supplies nitrous oxide gas.
  • a cylinder, a tank, or a curdle can be used as the high-pressure gas container 5.
  • the high-pressure gas container 5 is connected to the first supply line 6 via a nitrous oxide gas on / off valve 15.
  • the nitrous oxide gas on-off valve 15 is for opening / closing the first supply line 6 and for supplying / blocking nitrous oxide gas from the high-pressure gas container 5 (opening / closing means). Further, as the nitrous oxide gas on-off valve 15, not only the first supply line 6 can be opened and closed, but also the opening degree (including pressure and the like) can be adjusted.
  • the nitrous oxide gas on-off valve 15 can be a control valve with a flow rate adjustment (flow rate adjustment valve) capable of controlling the flow rate.
  • the nitrous oxide gas on / off valve 15 is electrically connected to a control unit 19 described later, and the control unit 19 can drive and control the nitrous oxide gas on / off valve 15.
  • the nitrous oxide gas on / off valve 15 is not limited to the configuration using the above-described control valve with flow rate adjustment (flow rate adjustment valve), but is a valve (open / close valve) that opens and closes the first supply line 6.
  • a configuration in which a regulator (flow rate regulator) for adjusting the flow rate of nitrous oxide gas flowing in the first supply line 6 is provided.
  • the first supply line 6 is a pipe (flow path) having one end connected to the high-pressure gas container 5 and the other end connected to the inlet side of the heat absorption side heat exchange unit 3.
  • the second supply line 7 is a pipe (flow path) whose one end side is connected to the outlet side of the heat absorption side heat exchange unit 3 and the other end side is connected to the inlet side (gas introduction port 2b) of the decomposition reaction unit 2. is there. Then, the first and second supply lines 6 and 7, nitrous oxide emitted from the high-pressure gas container 5 gas (N 2 O) nitrous supplies the decomposition reaction unit 2 oxide gas supply line (nitrous oxide Nitrogen gas supply means).
  • the third supply line 8 is a pipe (flow path) whose one end side is connected to the outlet side (gas exhaust port 2 c) of the decomposition reaction section 2 and the other end side is connected to the inlet side of the heat radiation side heat exchange section 4. is there.
  • the discharge line 9 is a pipe (flow path) whose one end is connected to the outlet side of the heat radiation side heat exchange unit 4.
  • the present invention provides a nitrogen gas supply for supplying nitrogen gas (N 2 ) to the decomposition reaction unit 2 in order to continuously decompose the nitrous oxide gas using the catalyst 1 in the decomposition reaction unit 2.
  • a line (nitrogen gas supply means) 16 for adjusting the flow rate of the nitrous oxide gas supplied to the decomposition reaction part 2, and a temperature measuring part for measuring the temperature of the catalyst 1.
  • (Temperature measuring means) 18 and a control part (control means) 19 for controlling each part are provided.
  • the nitrogen gas supply line 16 is a pipe (flow path) connected to the first supply line 6, and a high-pressure gas container 20 filled with nitrogen gas is connected to the other end side.
  • the nitrogen gas supply line 16 is a concentration adjusting means for adjusting the concentration of the nitrous oxide gas by introducing (adding) nitrogen gas into the nitrous oxide gas flowing in the first supply line 6. It has the function of
  • the high-pressure gas container 20 is a nitrogen gas supply source that supplies nitrogen gas.
  • a cylinder, a tank, or a curdle can be used as the high-pressure gas container 20.
  • the high-pressure gas container 20 is connected to the nitrogen gas supply line 16 via a nitrogen gas on-off valve 21.
  • the nitrogen gas on-off valve 21 is for opening / closing the nitrogen gas supply line 16 and for supplying / blocking the nitrogen gas from the high-pressure gas container 20 (open / close means).
  • the nitrogen gas on / off valve 21 may be one that not only opens and closes the nitrogen gas supply line 16 but also has an adjustable opening (including pressure and the like).
  • a control valve with a flow rate adjustment (flow rate adjustment valve) capable of controlling the flow rate is used for the nitrogen gas on-off valve 21.
  • the nitrogen gas on / off valve 21 is electrically connected to the control unit 19, and the nitrogen gas on / off valve 21 can be driven and controlled by the control unit 19.
  • the nitrogen gas on / off valve 21 is not limited to the configuration using the above-described control valve with a flow rate adjustment (flow rate adjustment valve), but separately from the valve (open / close valve) for opening and closing the nitrogen gas supply line 16.
  • the flow rate adjusting unit 17 is disposed between the gas introduction port 2 b of the decomposition reaction unit 2 and the second supply line 7.
  • the flow rate adjusting unit 17 may be any unit that can adjust the flow rate (introduction amount) of the nitrous oxide gas introduced into the decomposition reaction unit 2, for example, a regulator (flow rate adjuster) or a control valve with flow rate adjustment. (A flow control valve) or the like can be used.
  • the flow rate adjusting unit 17 is electrically connected to the control unit 19, and the control unit 19 can drive and control the flow rate adjusting unit 17.
  • the flow rate adjusting unit 17 is provided with a flow meter (flow rate measuring means) for measuring the flow rate of the nitrous oxide gas flowing through the flow rate adjusting unit 17, or a regulator or a control valve with such a flow meter. It is also possible to adjust the flow rate of the nitrous oxide gas introduced into the decomposition reaction unit 2 with high accuracy.
  • a flow meter flow rate measuring means
  • the temperature measurement unit 18 measures the temperature of the catalyst 1 directly or indirectly, is electrically connected to the control unit 19, and outputs a measurement result (measurement data) to the control unit 19.
  • the temperature measuring unit 18 shown in FIG. 1 is attached to the main body 2 a of the decomposition reaction unit 2, and can measure the temperature on the downstream side of the catalyst 1 while contacting the catalyst 1.
  • the temperature measuring unit 18 is not limited to the configuration shown in FIG. 1 described above, and may be configured to measure the temperature on the upstream (gas inlet 2b) side of the catalyst 1. This is preferable in detecting whether or not the catalyst 1 heated by the heater 13 has been heated to the decomposition start temperature before starting the decomposition of the nitrous oxide gas. And based on the measurement result by this temperature measurement part 18, when the catalyst 1 is heated to the said decomposition
  • the location which measures the temperature of the catalyst it is not necessarily limited to said location, For example, in order to measure the average temperature of the catalyst 1, the temperature of the center part of the catalyst 1 is measured. It is also possible to measure the temperatures at these multiple locations separately.
  • the temperature measuring unit 18 is not limited to the configuration in which the temperature of the catalyst 1 is directly measured.
  • the temperature measuring unit 18 may indirectly measure the temperature of the catalyst 1 by measuring the temperature of the main body 2a containing the catalyst 1. Is possible.
  • the temperature measuring unit 18 is not limited to the configuration that directly or indirectly measures the temperature of the catalyst 1 described above, but directly or indirectly determines the temperature of the cracked gas discharged from the gas discharge port 2c of the cracking reaction unit 2. It is good also as a structure to measure to. Furthermore, it is good also as a structure which measures the temperature of both these catalysts 1 and cracked gas.
  • thermometer using a thermocouple for example, a thermometer using a thermocouple, a non-contact type thermometer such as a radiation thermometer, a data logger, or the like can be used, but is not necessarily limited to these. Instead, it can be used by appropriately selecting from those that can measure the temperature of the catalyst 1 or cracked gas.
  • the control unit 19 is composed of a computer (CPU) or the like, and based on the measurement result (measurement data) from the temperature measurement unit 18, according to the control program recorded therein, the nitrous oxide gas on-off valve 15 and the nitrogen gas described above. It is possible to control the driving of the on-off valve 21 and the flow rate adjusting unit 17.
  • the catalyst 1 exposed to the high temperature and high pressure by the cracked gas, the members on the gas outlet 2c side, etc. may be deteriorated (for example, thermal fatigue or oxidation). There is.
  • the temperature of the cracked gas becomes too low it may be difficult to continue the self-decomposition of nitrous oxide. Further, the nitrous oxide is not decomposed and is discharged from the gas discharge port 2c of the decomposition reaction unit 2, or the NO x gas described above is generated in some cases. These gases cause the above-mentioned global warming and air pollution.
  • control unit 19 can control the temperature of the cracked gas within a range in which the decomposition of the nitrous oxide using the catalyst 1 is continued in the cracking reaction unit 2 so that such a problem does not occur. preferable.
  • control unit 19 controls the flow rate adjusting unit 17 based on the measurement result from the temperature measuring unit 18, and nitrous oxide supplied to the decomposition reaction unit 2. Adjust the gas flow rate.
  • control is performed to relatively increase the flow rate of the nitrous oxide gas supplied to the cracking reaction section 2.
  • the amount of nitrous oxide gas introduced into the decomposition reaction section 2 is increased, and the temperature of the decomposition gas is relatively increased by increasing the amount of decomposition (heat of decomposition) of the nitrous oxide gas decomposed in the decomposition reaction section 2.
  • control unit 19 controls the nitrogen gas on-off valve 21 based on the measurement result from the temperature measurement unit 18, and the first supply from the nitrogen gas supply line 16. The flow rate of the nitrogen gas supplied to the line 6 is adjusted.
  • control is performed to relatively increase the concentration of nitrous oxide gas. That is, the flow rate of the nitrogen gas supplied from the nitrogen gas supply line 16 to the first supply line 6 is relatively lowered, or the supply of the nitrogen gas from the nitrogen gas supply line 16 to the first supply line 6 is stopped. Control. Thereby, the addition of the nitrogen gas to the nitrous oxide gas flowing in the first supply line 6 can be stopped or the addition amount thereof can be reduced, and the concentration of the nitrous oxide gas can be relatively increased. As a result, the amount of decomposition (heat of decomposition) of the nitrous oxide gas decomposed in the decomposition reaction section 2 increases, so that the temperature of the decomposition gas can be relatively increased.
  • control is performed to relatively lower the concentration of nitrous oxide gas. That is, the flow rate of nitrogen gas supplied from the nitrogen gas supply line 16 to the first supply line 6 is relatively increased, or supply of nitrogen gas from the nitrogen gas supply line 16 to the first supply line 6 is started. Control. Thereby, the nitrogen gas is added to the nitrous oxide gas flowing in the first supply line 6 or the amount of the nitrous oxide gas is increased, and the concentration of the nitrous oxide gas is reduced while diluting the nitrous oxide gas with the nitrogen gas. It can be relatively low. As a result, the amount of decomposition (heat of decomposition) of the nitrous oxide gas decomposed in the decomposition reaction unit 2 is reduced, so that the temperature of the decomposition gas can be relatively lowered.
  • an inert gas such as helium (He), neon (Ne), argon (Ar), xenon (Xe), krypton (Kr), etc. It is also possible to adjust the concentration of the nitrous oxide gas by adding air (including dry air) or the like to the nitrous oxide gas.
  • the above-described temperature control of the cracked gas can be performed by combining the methods using (1) and (2).
  • the above-described temperature control of the cracked gas can be stably performed with a simple configuration.
  • you may perform temperature control of cracked gas using the method of other than that.
  • NO x measurement means for measuring the concentration of NO x in the decomposition gas.
  • concentration of NO x gas such as undecomposed nitrous oxide (N 2 O), nitric oxide (NO), nitrogen dioxide (NO 2 ), etc. contained in the cracked gas, It is possible to accurately control the temperature of the cracked gas.
  • NO x removing means means for removing NO x contained in the cracked gas.
  • the NO x removal unit for example, by adding ammonia (NH 3) decomposition gas containing NO x, and selective reaction (reduction) is not ammonia and NO x by denitration catalyst, water (H 2 A denitration apparatus that decomposes into O) and nitrogen (N 2 ) can be used.
  • NH 3 ammonia
  • H 2 A denitration apparatus that decomposes into O
  • N 2 nitrogen
  • an optimum one may be selected from conventionally known ones.
  • the NO x removal means a NO x decomposition catalyst capable of directly decomposing NO x contained in the cracked gas may be used.
  • the decomposition reaction unit 2 stops the decomposition of the nitrous oxide gas using the catalyst 1
  • the decomposition reaction unit 2 is stopped after the supply of the nitrous oxide gas to the decomposition reaction unit 2 is stopped. It is preferable to supply nitrogen gas to
  • control unit 19 controls to close the nitrous oxide gas on-off valve 15 to stop the supply of nitrous oxide gas to the decomposition reaction unit 2 and supply from the nitrogen gas supply line 16. Only the nitrogen gas is introduced into the decomposition reaction section 2.
  • the control unit 19 introduces nitrogen gas into the decomposition reaction unit 2 for a certain period of time, that is, a time sufficient to remove the decomposition gas remaining in the catalyst 1, and then closes the nitrogen gas on-off valve 21. The supply of nitrogen gas to the decomposition reaction unit 2 is stopped.
  • an inert gas such as He, Ne, Xe, Ar, Kr, air (including dry air), or the like. It is also possible to introduce into the decomposition reaction part 2.
  • step S ⁇ b> 101 before starting the decomposition of nitrous oxide, the heater 13 is driven to heat (preheat) the catalyst 1.
  • step S102 based on the temperature of the catalyst 1 measured by the temperature measuring unit 18, the control unit 19 determines whether or not the catalyst 1 has been heated to the decomposition start temperature. If it is determined that the catalyst 1 has been heated to the decomposition start temperature, the process proceeds to step S103, and the driving of the heater 13 is stopped in step S103. On the other hand, when it is determined that the catalyst 1 is not heated to the decomposition start temperature, the heating of the catalyst 1 by the heater 13 is continued until the catalyst 1 reaches the decomposition start temperature.
  • step S104 nitrous oxide gas is supplied to the decomposition reaction section 2, and the decomposition reaction section 2 decomposes the nitrous oxide gas using the catalyst 1.
  • the flow rate, concentration, and the like of the nitrous oxide gas supplied to the decomposition reaction unit 2 are preset values.
  • step S105 based on the temperature of the catalyst 1 (or cracked gas) measured by the temperature measuring unit 18, the controller 19 sets a value (range) in which the temperature of the catalyst 1 (or cracked gas) is set in advance. It is determined whether or not the number is exceeded. When it is determined that the temperature of the catalyst 1 (or cracked gas) has exceeded the set value (range), the process proceeds to step S106. On the other hand, if it is determined that the temperature of the catalyst 1 (or cracked gas) is within the set value (range), the process proceeds to step S110.
  • step S106 the control unit 19 determines (comparison) whether the temperature of the catalyst 1 (or cracked gas) is higher or lower than a set value (range).
  • step S107 the control unit 19 is supplied to the cracking reaction unit 2.
  • the nitrous oxide gas flow rate or the concentration of the nitrous oxide gas is adjusted to decrease. Then, after the adjustment, the process proceeds to step S109.
  • step S108 the control unit 19 is supplied to the cracking reaction unit 2.
  • the nitrous oxide gas flow rate or the concentration of the nitrous oxide gas is adjusted to increase. Then, after the adjustment, the process proceeds to step S109.
  • step S107 or step S108 for example, a predetermined value within a range in which the set value of the flow rate of the nitrous oxide gas supplied to the decomposition reaction unit 2 or the set value of the concentration of the nitrous oxide gas can be adjusted. It is divided into the number of stages, and the set value is lowered or increased by one stage from the current stage.
  • step S109 based on the temperature of the catalyst 1 (or cracked gas) measured by the temperature measuring unit 18, the controller 19 determines whether the temperature of the catalyst 1 (or cracked gas) has returned to the set value (range). Determine whether or not. And when it determines with the temperature of the catalyst 1 (or decomposition gas) having returned to the setting value (range), it progresses to step S110.
  • step S106 determines whether the temperature of the catalyst 1 (or cracked gas) has returned to the set value (range).
  • step S110 determines that it is abnormal and forcibly proceeds to step S110 (not shown in FIG. 3).
  • step S110 the control unit 19 determines whether or not to stop the supply of nitrous oxide gas.
  • Examples of the case where the supply of nitrous oxide gas is stopped include a case where a stop command is received from the outside, and a case where it is determined as abnormal in step S109. And when stopping supply of nitrous oxide gas, it progresses to step S111. On the other hand, when the supply of nitrous oxide gas is not stopped, the process returns to step S105, and the temperature measurement of the catalyst 1 (or decomposition gas) by the temperature measurement unit 18 is continued.
  • step S111 after the supply of nitrous oxide gas is stopped, the process proceeds to step S112, and in this step S112, nitrogen gas is supplied to the decomposition reaction unit 2. Thereby, the cracked gas which nitrogen gas stayed in the catalyst 1 is pushed out, and the cracked gas stayed in the catalyst 1 can be removed.
  • the heat transport apparatus shown in FIG. 1 can continuously decompose nitrous oxide using the catalyst 1 in the decomposition reaction section 2 while controlling the temperature of the decomposition gas. It is.
  • the measurement data measured by the temperature measurement unit 18 and the determination result of the control unit 19 based on the measurement data may be displayed on a monitor (not shown) or output to a printer, for example.
  • a monitor not shown
  • a printer for example.
  • step S109 when it is determined that there is an abnormality in step S109, it may be notified as necessary.
  • the notification method is not particularly limited, and for example, an alarm can be issued or a display can be performed.
  • Nitrous oxide used in the present invention can be produced industrially.
  • examples of the method for industrially producing nitrous oxide include methods using the following (1) to (3).
  • nitrous oxide produced industrially for example, high purity nitrous oxide having a purity of 99.9 (3N) to 99.999 (5N)%, purity of 97.0% or more (Japan Pharmacopoeia)
  • high purity nitrous oxide having a purity of 99.9 (3N) to 99.999 (5N)%, purity of 97.0% or more Japanese Pharmacopoeia
  • examples thereof include medical nitrous oxide and industrial nitrous oxide having a purity of 98% or more.
  • examples of the method for producing nitrous oxide include the following methods (4) to (10).
  • Nitric acid is reduced with zinc or tin, or with sulfurous acid gas.
  • the manufactured nitrous oxide is filled in the high-pressure gas container 5 by a gas maker, and then sent to the heat transport device shown in FIG. 1 for use.
  • the high-pressure gas container 5 can be used repeatedly by being returned to the gas manufacturer after use and being refilled.
  • the supply method of the nitrous oxide gas is not limited to the supply method using the high-pressure gas container 5 (replacement of the high-pressure gas container 5).
  • a method of supplying to the gas container 5 can be used.
  • the nitrogen gas supply method is not limited to the method of supplying using the high-pressure gas container 20 (replacement of the high-pressure gas container 20), and the same method as the above-described method of supplying nitrous oxide gas is used. It is possible to supply.
  • the decomposition start temperature of the nitrous oxide gas can be lowered. And after decomposition
  • the temperature of the catalyst 1 is preferably in the range of 200 to 600 ° C. from the viewpoint of catalyst activity, and more preferably in the range of 350 to 450 ° C. from the viewpoint of ease of decomposition reaction. That is, in the present invention, it is preferable to perform preheating by the heater 13 and temperature control of the cracked gas by the control unit 19 so that the temperature of the catalyst 1 falls within such a range.
  • nitrous oxide itself self-decomposes at about 500 ° C. or higher, by keeping the decomposition reaction part 2 at or above the self-decomposition temperature, nitrous oxide gas is continuously decomposed without using the catalyst 1. It is also possible to do this. However, it is known that when nitrous oxide gas is self-decomposed without using the catalyst 1, NO x gas is generated as a decomposition byproduct. Therefore, in the present invention, it is preferable to use the catalyst 1 in order to prevent the generation of the NO x gas. In addition, the said catalyst 1 can be used even if it is more than the self-decomposition temperature of nitrous oxide gas.
  • the temperature of the nitrous oxide gas may be a temperature at which the nitrous oxide gas does not liquefy, and can usually be used at room temperature or lower.
  • nitrous oxide gas can be preheated to a temperature higher than room temperature and used. For example, when the concentration of nitrous oxide gas is low, decomposition of the nitrous oxide gas can be promoted by preheating the nitrous oxide gas.
  • the concentration of nitrous oxide gas is not particularly limited.
  • the concentration of nitrous oxide gas is adjusted within the range of 1 to 100%, and when more energy needs to be obtained, it exceeds 50% to 100%.
  • % Adjusted in the range of%, and further adjusted in the range of more than 70% to 100% can be used. Further, by adjusting the concentration of the nitrous oxide gas described above, it is possible to adjust the decomposition reaction rate of the nitrous oxide gas and the like.
  • N 2 nitrogen
  • concentration of nitrous oxide N 2 O contained in the fuel gas
  • N 2 oxygen
  • the oxygen concentration is preferably in the range of about 18 to 24%. In that case, the concentration of nitrous oxide gas is about 44 to 63%. It is preferable to be in the range.
  • a nitrous oxide gas having a concentration of less than 44% that is, a nitrous oxide gas having a low concentration.
  • the energy (energy density) generated by the decomposition of the nitrous oxide gas becomes low, the catalyst exposed to high temperature and high pressure by the decomposition gas described above by making the decomposition reaction of the nitrous oxide gas gentle. 1 and degradation (for example, thermal fatigue and oxidation) of each member such as the decomposition reaction portion 2 can be suppressed. That is, in the present invention, it is possible to adjust the concentration of the nitrous oxide gas in consideration of the heat resistance and oxidation resistance of the respective materials such as the catalyst 1 and the decomposition reaction portion 2 described above.
  • a nitrous oxide gas having a concentration of more than 63% that is, a nitrous oxide gas having a high concentration.
  • energy (energy density) generated by decomposition of nitrous oxide gas can be increased.
  • the catalyst 1 can be used to continuously decompose the nitrous oxide gas.
  • high-purity for example, purity 99.9 (3N) to 99.999 (5N)%
  • nitrous oxide gas for example less than 97% purity.
  • the above-mentioned concentration adjustment of nitrous oxide gas by nitrogen gas is a method of adding nitrogen gas or the like to nitrous oxide gas before decomposition of nitrous oxide gas, A method of adding nitrogen gas or the like may be used. Further, nitrous oxide gas whose concentration has been adjusted in advance may be used.
  • the nitrogen gas supply line 16 is not limited to the one connected to the first supply line 6 described above, but is connected to the second supply line 7, the third supply line 8, the discharge line 9, and the like. It may be a thing.
  • nitrous oxide contained in the nitrous oxide gas Components other than nitrous oxide contained in the nitrous oxide gas are mixed during the production of nitrous oxide, which will be described later, in addition to nitrogen added for adjusting the concentration of nitrous oxide described above. And unreacted substances, by-products, air, inevitable impurities, and the like.
  • an oxygen concentration meter for measuring the oxygen concentration in the cracked gas may be provided.
  • oxygen measuring means oxygen measuring means
  • the space velocity (Space Velocity) of the nitrous oxide gas introduced into the decomposition reaction unit 2 may be set to an optimum value according to the design, for example, in the range of 10 to 140,000 hr ⁇ 1 , Preferably, it can be set in the range of 100 to 10,000 hr ⁇ 1 .
  • the cracked gas discharged from the discharge line 9 can also be used for fuel combustion.
  • the fuel is combustible using oxygen contained in the cracked gas, for example, in addition to fossil fuels such as petroleum, coal, and natural gas, alternative fuels such as biomass fuel are used. can do.
  • alternative fuels such as biomass fuel are used. can do.
  • a heat transport device that enables the use of nitrous oxide as energy friendly to the global environment and enables heat transport using the energy generated by the decomposition of the nitrous oxide, and It is possible to provide a heat transport method.
  • the cooling heat (low temperature) accompanying the adiabatic expansion of nitrous oxide and the decomposition heat (high temperature) generated by the decomposition of this nitrous oxide two kinds of levels can be obtained from one kind of gas. It is possible to obtain a temperature range (low temperature and high temperature).
  • nitrous oxide itself, which is an energy source (heat source)
  • heat source heat source
  • the cracked gas can be used as a heat medium.
  • Heat transport apparatus it is possible to obtain a cold air (cold) T L described above, a hot air (hot) T H, and can be variously applied to refrigeration and air conditioning fields.
  • a heat transport device to which the present invention is applied can be applied to air conditioning equipment such as an air conditioner that performs cooling and heating, air conditioning equipment, and the like.
  • the present invention can be applied to heating equipment, heating equipment, and the like that perform hot water supply, hot water, drying, and the like.
  • the cooling field in addition to cooling, it can be applied to cooling equipment and cooling equipment for performing refrigeration, freezing, cold water, ice making, and the like.
  • the heat transport apparatus to which the present invention is applied can be applied to a variety of sizes from large to small. In addition to its use for factories (industrial) and homes (households), it can be used in various fields, and it can be designed to suit the application, such as installation (stationary), portable, and portable. do it.
  • a conversion unit (conversion means) 30 that converts a temperature difference into electric power or power is provided.
  • the high temperature side 30a of the conversion unit 30 can be heated by the heat dissipation side heat exchange unit 4 as a heating unit, and the low temperature side 30b of the conversion unit 30 can be cooled by the heat absorption side heat exchange unit 3 as a cooling unit. It is.
  • the conversion unit 30 includes, for example, a thermoelectric conversion element that converts a temperature difference (thermal energy) into electric power (electric energy), a Stirling engine that converts a temperature difference (thermal energy) into power (kinetic energy), a heat pipe turbine, and the like. Can be used.
  • FIG. 5 a heat transport apparatus including a heat pipe turbine 31 as illustrated in FIG. 5 will be described.
  • the heat transport apparatus shown in FIG. 5 is roughly equipped with the structure similar to the heat transport apparatus shown in the said FIG.1 and FIG.4. Therefore, in the heat transport apparatus shown in FIG. 5, the description of the same parts as those of the heat transport apparatus shown in FIGS. 1 and 4 is omitted and the same reference numerals are given in the drawings.
  • the heat transport device shown in FIG. 5 is an engine device including a heat pipe turbine 31 (corresponding to the conversion unit 30) that converts a temperature difference into power, and further generates power by driving the heat pipe turbine 31. It is a power generator provided with the generator 32 to do.
  • the heat pipe turbine 31 includes a heat pipe 33 having a hollow ring shape as a whole, and the heat pipe 33 is filled with a condensable working fluid (steam source) L in a state where the inside is vacuum degassed. Has a structured. Further, the heat pipe 33 is provided with a storage portion 34 for storing the working fluid L.
  • water steam
  • a fluid having a boiling point lower than that of water such as ammonia or an organic medium such as normal pentane.
  • the condensed (liquefied) working fluid L (shown in the direction indicated by the solid line arrow in FIG. 6) supplied from the storage section 34 side is radiated.
  • An evaporation unit 35 that is heated and evaporated by heat exchange with the side heat exchange unit 4 is provided.
  • the other side of the heat pipe 33 across the storage portion 34 indicates the direction of flow of the evaporated (vaporized) working fluid L supplied from the evaporation portion 35 side (broken arrows in FIG. 6). ) Is condensed by cooling by heat exchange with the heat absorption side heat exchange unit 3.
  • the evaporation unit 35 and the condensation unit 36 are provided with heat sinks (fins) 37a and 37b for improving the thermal conductivity between the heat radiation side heat exchange unit 4 and the heat absorption side heat exchange unit 3, respectively. Yes.
  • a turbine section 38 that is rotationally driven by the vaporized working fluid L is provided between the evaporation section 35 and the condensation section 36 of the heat pipe 33.
  • the generator 70 is connected to the turbine unit 38.
  • nitrous oxide gas (N 2 O) discharged from the high-pressure gas container 5 and adiabatically expanded is supplied to the heat radiation side heat exchange unit 3 through the first supply line 6.
  • this nitrous oxide gas passes the inside of the heat absorption side heat exchange part 3, the condensing part 36 of the said heat pipe turbine 31 is cooled. That is, in the heat absorption side heat exchanging unit 3, the working fluid L flowing in the condensing unit 36 is cooled by using the cooling heat accompanying the adiabatic expansion of nitrous oxide.
  • the nitrous oxide gas discharged from the heat absorption side heat exchange unit 3 is supplied to the decomposition reaction unit 2 through the second supply line 7. And while this nitrous oxide gas passes through the inside of the decomposition reaction section 2, decomposition by the catalyst 1 is performed.
  • the decomposition gas (N 2 , O 2 ) of nitrous oxide obtained by decomposing nitrous oxide gas in the decomposition reaction unit 2 is supplied to the heat radiation side heat exchange unit 4 through the third supply line 8.
  • this cracked gas passes the inside of the thermal radiation side heat exchange part 4, the evaporation part 35 of the said heat pipe turbine 31 is heated. That is, in the heat radiation side heat exchanging unit 4, the working fluid L in the evaporation unit 35 is heated using decomposition heat generated by decomposition of nitrous oxide.
  • the cracked gas is discharged from the discharge line 9.
  • the working fluid L evaporated in the evaporator 35 flows to the condenser 36 and condenses.
  • the working fluid L circulates while repeating this. That is, heat transport is performed by absorbing and releasing the latent heat of the working fluid L.
  • the flowing working fluid L can rotate the turbine portion 38 to obtain power. Furthermore, electric power can be obtained by rotationally driving the generator 32 connected to the turbine section 38.
  • the above heat is obtained by utilizing the cooling heat accompanying the above-described adiabatic expansion of nitrous oxide and the decomposition heat generated by the decomposition of this nitrous oxide.
  • a large temperature difference can be generated between the evaporator 35 and the condenser 36 of the pipe turbine 31. And it is possible to obtain a large output (power and electric power) by utilizing such a temperature difference before and after decomposition of nitrous oxide gas.
  • the heat transport device shown in FIG. 5 is not necessarily limited to the configuration including the heat pipe turbine 31.
  • the heat pipe turbine 31 may be of various types such as a siphon type and a wick type. Can be used.
  • various types such as a single pipe type and a loop type can be used.
  • the concentration of nitrous oxide contained in exhaust gas discharged from factories and incineration facilities is 10% or less, while the concentration of nitrous oxide contained in excess anesthetic gas discharged from the operating room excludes excess anesthetic gas. Although it is somewhat diluted with compressed air in the apparatus, it is 70% or less, which is a very high concentration.
  • the nitrous oxide decomposition catalyst of the present invention is a catalyst that can cope with the decomposition of nitrous oxide having a low concentration to a high concentration.
  • the nitrous oxide decomposition catalyst of the present invention can be decomposed at a relatively low temperature, is less susceptible to activity degradation due to moisture even in the presence of moisture, and reduces the generation amount of NO x below an allowable concentration.
  • the amount of NO x generated can be reduced to about 1/10 to 1/100 or less of the conventional cracking catalyst.
  • the nitrous oxide decomposition catalyst of the present invention comprises any one of the following catalysts [1] to [3] containing three kinds of metals, aluminum, magnesium and rhodium as essential components: [1] aluminum, magnesium and rhodium [2] a catalyst in which magnesium and rhodium are supported on an alumina carrier, [3] a carrier in which a spinel crystalline composite oxide is formed of at least a part of aluminum and magnesium.
  • the following [4] containing, as essential components, a catalyst on which rhodium is supported, and at least one metal selected from the group consisting of two metals, aluminum and rhodium, and zinc, iron, manganese and nickel.
  • a carrier selected from the group consisting of alumina, silica, zirconia, ceria, titania and tin oxide can be used
  • alumina A carrier selected from zirconia, ceria, titania and tin oxide can be used.
  • Carriers having a surface area of about 30 to 300 m 2 / g can be used, and there is no particular limitation on the shape, but depending on the reactor or reaction method, it is suitable for each of granular, powder, honeycomb, etc. You can choose the shape.
  • the aluminum and magnesium supported on the carrier contain aluminum in an atomic ratio of at least 2 with respect to magnesium.
  • Magnesium is preferably contained in an amount of 0.1 to 20.0% by mass based on the metal atom.
  • the spinel-type crystalline composite oxide is formed, for example, by firing a carrier supporting aluminum and magnesium.
  • the spinel structure is a structure found in an oxide having a chemical formula of XY 2 O 4 and belongs to a cubic system, and Al and Mg are known to form a MgAl 2 O 4 spinel structure.
  • the reason for the nitrous oxide decomposition catalyst of the present invention is not clear, but at least a part of aluminum forms a spinel crystalline composite oxide with magnesium, thereby improving the resolution of nitrous oxide. It is considered that the effect of reducing the generation amount of NO x is exhibited.
  • At least one metal selected from the group consisting of zinc, iron, manganese and nickel and aluminum supported on the carrier is selected from the group consisting of zinc, iron, manganese and nickel. It is preferable that at least 2 or more are contained by atomic ratio with respect to at least 1 type of metal. In addition, it is preferable that at least one metal selected from the group consisting of zinc, iron, manganese and nickel is contained in an amount of 0.1 to 40.0% by mass in terms of metal atoms.
  • At least a part of aluminum forms a spinel crystalline composite oxide with at least one metal selected from the group consisting of zinc, iron, manganese, and nickel.
  • the spinel crystalline composite oxide can be produced by firing a carrier supporting aluminum and at least one metal selected from the group consisting of zinc, iron, manganese and nickel.
  • M Zn, Fe, Mn, Ni.
  • the reason for the nitrous oxide decomposition catalyst of the present invention is not clear, but at least a part of aluminum is at least one metal selected from the group consisting of zinc, iron, manganese and nickel, and a spinel crystalline composite. that forms the oxides, thereby improving the resolution of nitrous oxide, is believed to exert an effect of reducing the amount of generation of NO x.
  • the carrier used for the catalyst of [2] is alumina, and the alumina is not particularly limited, but those having a surface area of about 50 to 300 m 2 / g can be used.
  • the magnesium supported on the alumina preferably contains aluminum in an atomic ratio of at least 2 with respect to magnesium. Magnesium is preferably contained in an amount of 0.1 to 20.0% by mass in terms of metal atoms. Moreover, it is preferable that at least a part of aluminum forms a spinel crystalline composite oxide with magnesium.
  • the carrier used for the catalyst of [5] is alumina, and the alumina is not particularly limited, but those having a surface area of about 50 to 300 m 2 / g can be used.
  • At least one metal selected from the group consisting of zinc, iron, manganese and nickel supported on alumina is an atomic ratio of aluminum to at least one metal selected from the group consisting of zinc, iron, manganese and nickel. It is preferable that at least two or more are included. It is preferable that at least one metal selected from the group consisting of zinc, iron, manganese and nickel is contained in an amount of 0.1 to 40.0% by mass based on the metal atom.
  • at least a part of aluminum forms a spinel crystalline composite oxide with at least one metal selected from the group consisting of zinc, iron, manganese, and nickel.
  • a catalyst in which a spinel-type crystalline composite oxide is formed of at least a part of aluminum and magnesium is used as the catalyst [3].
  • the atomic ratio of aluminum and magnesium in the catalyst of [3] is preferably such that aluminum is contained in an atomic ratio of at least 2 with respect to magnesium.
  • Magnesium is preferably contained in an amount of 0.1 to 20.0% by mass based on the metal atom.
  • the catalyst [6] uses a carrier in which a spinel crystalline composite oxide is formed of at least a part of aluminum and at least one metal selected from the group consisting of zinc, iron, manganese and nickel.
  • the atomic ratio of aluminum and at least one metal selected from the group consisting of zinc, iron, manganese and nickel in the catalyst of [6] is at least 1 selected from the group where aluminum is zinc, iron, manganese and nickel It is preferable that at least 2 or more is contained by atomic ratio with respect to the metal of seed
  • the rhodium contained in the nitrous oxide decomposition catalyst of the present invention is preferably 0.05 to 10% by mass in terms of metal atoms in any of the catalysts [1] to [6]. More preferably, the content is 0.1 to 6.0% by mass. Although it is possible to improve the catalyst activity at low temperature by increasing the amount of rhodium supported, it is not preferable to support 10% by mass or more in view of the cost of the catalyst, and 0.05% by mass or less. Sufficient nitrous oxide decomposition activity cannot be obtained.
  • nitrous oxide decomposition catalyst of the present invention Next, the method for producing the nitrous oxide decomposition catalyst of the present invention will be described.
  • Various production methods can be used for the nitrous oxide decomposition catalyst of the present invention.
  • (1) impregnation method, (2) coprecipitation method, (3) kneading method, and the like can be used.
  • the production method of the nitrous oxide decomposition catalyst of the present invention will be described.
  • the support selected from the group consisting of alumina, zirconia, ceria, titania and tin oxide is firstly at least one selected from the group consisting of aluminum and zinc, iron, manganese and nickel. Impregnation with inorganic acid salts (nitrate, hydrochloride, sulfate, etc.) or organic acid salts (oxalate, acetate, etc.) of seed metals.
  • an alumina carrier is impregnated with a magnesium inorganic acid salt (nitrate, hydrochloride, sulfate, etc.) or an organic acid salt (oxalate, acetate, etc.).
  • an inorganic support nitrate, hydrochloride, sulfate, etc.
  • an organic salt of at least one metal selected from the group consisting of zinc, iron, manganese, and nickel is used on an alumina support. Impregnate with acid salts (oxalate, acetate, etc.).
  • acid salts oxalate, acetate, etc.
  • the at least one metal salt selected from the group consisting of an aluminum salt, a magnesium salt and zinc, iron, manganese, and nickel it is preferable to use a nitrate.
  • the amount supported on the carrier of aluminum and magnesium is preferably such that aluminum is supported so that the atomic ratio with respect to magnesium is 2 or more. It is preferable to make it 0.1 to 20.0% by mass.
  • the amount of aluminum supported on at least one metal carrier selected from the group consisting of aluminum, zinc, iron, manganese and nickel is aluminum, zinc, iron, manganese and nickel. It is preferably supported so that the atomic ratio with respect to at least one metal selected from the group consisting of 2 or more is supported, and the supported amount of at least one metal selected from the group consisting of zinc, iron, manganese and nickel However, it is preferable to be 0.1 to 40.0% by mass of the total catalyst.
  • magnesium is supported so that the atomic ratio to aluminum is 1 ⁇ 2 or less, and the amount of magnesium supported is 0.1-20. It is preferable to be 0% by mass.
  • at least one metal selected from the group consisting of zinc, iron, manganese and nickel is supported so that the atomic ratio with respect to aluminum is 1 ⁇ 2 or less.
  • the supported amount of at least one metal selected from the group consisting of zinc, iron, manganese and nickel is 0.1 to 40.0% by mass of the total catalyst.
  • the carrier After supporting the desired metal salt on the carrier, the carrier is dried and fired to contain, for example, aluminum and magnesium, and at least part of the aluminum forms a spinel-type crystalline composite oxide with magnesium.
  • a carrier can be obtained, and this carrier is used as the carrier for the catalyst of [1].
  • it contains aluminum and at least one metal selected from the group consisting of zinc, iron, manganese and nickel, and at least a part of aluminum is selected from the group consisting of zinc, iron, manganese and nickel.
  • a support in which a spinel-type crystalline composite oxide is formed with at least one kind of metal can be obtained, and this support is used as a support for the catalyst of [4].
  • the drying temperature after impregnating the aluminum salt and magnesium salt in the catalyst [1], the aluminum salt in the catalyst [4], and at least one metal salt selected from the group consisting of zinc, iron, manganese and nickel is not particularly limited, but is preferably in the temperature range of 80 to 150 ° C, more preferably in the temperature range of 100 to 130 ° C.
  • the drying atmosphere is not particularly limited, and nitrogen or air can be used.
  • the drying time is not particularly limited, but when using the impregnation method, it may usually be about 2 to 4 hours.
  • Calcination of the carrier after impregnation and drying can be performed in a temperature range of 400 to 900 ° C., preferably 500 to 700 ° C.
  • the firing time is not particularly limited, but may be about 1 to 10 hours, preferably about 2 to 4 hours, and the firing temperature may be changed stepwise. Long-term firing is economically undesirable because the effect is saturated, and short-term firing may be less effective.
  • baking can be performed using a baking furnace, a muffle furnace, etc., and any of nitrogen or air may be used as a distribution gas at this time.
  • a rhodium salt is supported on the carrier obtained by firing.
  • an inorganic acid salt nitrate, hydrochloride, sulfate, etc.
  • an organic acid salt oxalate, acetate, etc.
  • the rhodium salt for example, in the case of producing a catalyst containing three kinds of metals, aluminum, magnesium and rhodium, as essential components, at least a part of the aluminum obtained using the above method is magnesium and It is preferably performed on the carrier forming the spinel crystalline composite oxide, but it may be performed simultaneously with the step of impregnating and supporting aluminum and magnesium on the carrier or the step of impregnating and supporting magnesium on the alumina carrier. Further, the supported amount of rhodium is preferably 0.05 to 10% by mass of the whole catalyst.
  • the step of supporting the rhodium salt is for producing a catalyst containing as essential components at least one metal selected from the group consisting of two metals, aluminum and rhodium, and zinc, iron, manganese and nickel.
  • the aluminum obtained by the above method is used as a carrier that forms a spinel crystalline composite oxide with at least one metal selected from the group consisting of zinc, iron, manganese, and nickel.
  • it is carried out with respect to the step of impregnating and supporting at least one metal selected from the group consisting of aluminum and zinc, iron, manganese and nickel on the support, or from zinc, iron, manganese and nickel on the alumina support.
  • the supported amount of rhodium is preferably 0.05 to 10% by mass of the whole catalyst.
  • the catalyst of [3] is produced by supporting a rhodium salt on the support in the same manner as described above. can do.
  • a rhodium salt is added to the support.
  • the catalyst of [6] can be produced by supporting the catalyst.
  • the rhodium-supported catalyst precursor is dried under the same drying conditions as described above, and the dried catalyst precursor is calcined.
  • the firing temperature is preferably 200 to 500 ° C, more preferably 300 to 400 ° C.
  • the catalyst obtained by calcination can be used as a nitrous oxide decomposition catalyst, it is preferable to further perform a reduction treatment, and a rhodium-containing catalyst with higher activity can be obtained by carrying out the reduction treatment.
  • the reduction treatment can be performed by, for example, (1) a method of re-drying after hydrazine reduction and firing, or (2) a method of hydrogen reduction, and a method of hydrogen reduction is preferably used.
  • the reduction temperature is preferably 200 to 500 ° C., more preferably 300 to 400 ° C.
  • the reduction time is not particularly limited, the treatment can be performed in about 1 to 10 hours, preferably about 2 to 4 hours. Moreover, you may perform a reduction process, without performing a baking process, and a rhodium containing catalyst with high activity can be obtained also in this case.
  • a method for producing a catalyst by carrying out a reduction treatment without performing a calcination treatment a method in which hydrogen is reduced at a temperature of 200 to 500 ° C. is preferable.
  • the above catalysts [3] and [6] can be produced.
  • a method for producing the catalyst of [3] using the coprecipitation method for example, ammonia water is dropped into an aqueous solution containing aluminum and magnesium nitrate to neutralize and precipitate, and if necessary, left to age and washed with filtered water. Check that the water has been thoroughly washed with the conductivity of the washing water. Next, after drying for about 10 to 12 hours under the same conditions as in the impregnation method, the obtained dried body is pulverized and molded with uniform particle sizes. Further, a carrier in which at least a part of aluminum forms a spinel-type crystalline composite oxide with magnesium is obtained by baking in a nitrogen or air atmosphere under the same conditions as in the impregnation method.
  • the amount of aluminum and magnesium is preferably such that aluminum has an atomic ratio of 2 or more with respect to magnesium, and magnesium is preferably contained in an amount of 0.1 to 20.0% by mass of the total catalyst in terms of metal atoms. .
  • At least a part of the aluminum thus obtained carries a rhodium salt on a carrier that forms a spinel-type crystalline composite oxide with magnesium.
  • the method, the amount supported, and the subsequent treatment method are the same as the above impregnation method. Can be done.
  • an aqueous solution containing an aluminum nitrate and at least one metal nitrate selected from the group consisting of zinc, iron, manganese and nickel is used as a method for producing the catalyst of [6] using the coprecipitation method.
  • Aqueous ammonia is added dropwise to neutralize and precipitate, and if necessary, aged as it is, washed with filtered water, and it is confirmed that it has been sufficiently washed with the conductivity of the washing water.
  • the obtained dried body is pulverized and molded with uniform particle sizes.
  • At least a part of aluminum is selected from the group consisting of zinc, iron, manganese and nickel and spinel crystallinity.
  • a carrier forming a complex oxide is obtained.
  • the amount of at least one metal selected from the group consisting of aluminum and zinc, iron, manganese and nickel is an atomic ratio of aluminum to at least one metal selected from the group consisting of zinc, iron, manganese and nickel.
  • at least one metal selected from the group consisting of zinc, iron, manganese and nickel is contained in an amount of 0.1 to 40.0% by mass in terms of metal atoms. It is preferable.
  • At least a portion of the aluminum thus obtained carries a rhodium salt on a carrier that forms a spinel crystalline composite oxide with at least one metal selected from the group consisting of zinc, iron, manganese and nickel.
  • the method, the loading amount and the subsequent treatment method can be carried out in the same manner as the above impregnation method.
  • Catalyst production method using a kneading method [3] and [6] catalysts can be produced using a kneading method.
  • a method for producing the catalyst of [3] using the kneading method for example, water is added to alumina and / or aluminum hydroxide and magnesium oxide, magnesium hydroxide and / or magnesium salt, for example, if necessary, The mixture obtained by mechanical mixing can be dried, and further subjected to a firing treatment under the same conditions as in the impregnation method to obtain the spinel crystalline composite oxide.
  • the amount of aluminum and magnesium is preferably such that aluminum has an atomic ratio of 2 or more with respect to magnesium, and magnesium is preferably contained in an amount of 0.1 to 20.0% by mass of the total catalyst in terms of metal atoms. .
  • At least a portion of the aluminum thus obtained carries a rhodium salt on a fired body that forms a spinel-type crystalline composite oxide with magnesium.
  • the method, the amount supported, and the subsequent treatment method are the same as the above impregnation method. This method can be used.
  • the rhodium salt may be added in advance when alumina or the like is mechanically mixed.
  • Examples of the method for producing the catalyst of [6] using the kneading method include at least one oxide selected from the group consisting of alumina and / or aluminum hydroxide and zinc, iron, manganese and nickel, and hydroxylation.
  • at least one oxide selected from the group consisting of alumina and / or aluminum hydroxide and zinc, iron, manganese and nickel, and hydroxylation For example, water is added to the product and / or metal salt, if necessary, and the mixture obtained by mechanical mixing is dried, and further subjected to a firing treatment under the same conditions as in the impregnation method. An oxide can be obtained.
  • the amount of at least one metal selected from the group consisting of aluminum and zinc, iron, manganese and nickel is such that aluminum is based on at least one metal selected from the group consisting of zinc, iron, manganese and nickel.
  • the atomic ratio is preferably 2 or more, and at least one metal selected from the group consisting of zinc, iron, manganese and nickel is 0.1 to
  • At least a portion of the aluminum thus obtained carries a rhodium salt on a fired body that forms a spinel-type crystalline composite oxide with at least one metal selected from the group consisting of zinc, iron, manganese, and nickel.
  • a rhodium salt may be added in advance when alumina or the like is mechanically mixed.
  • the decomposition reaction of nitrous oxide is performed using the decomposition catalyst of the present invention, it can be performed in a temperature range of 200 to 600 ° C.
  • the decomposition catalyst of the present invention and nitrous oxide may be contacted in the gas phase, preferably in the temperature range of 300 to 500 ° C, more preferably in the temperature range of 350 to 450 ° C. If the temperature is lower than 200 ° C., decomposition of nitrous oxide is not sufficient, and if it is 600 ° C. or higher, the catalyst life tends to be short, which is not preferable.
  • the catalyst bed system is not particularly limited, but a fixed bed is generally preferably used.
  • the catalytic activity of the conventional palladium catalyst decreases due to the influence of moisture and does not return to the original activity even when the moisture is removed, whereas the cracking catalyst of the present invention has 1 to 3% moisture coexistence. Although the activity may slightly decrease depending on the condition, it has a characteristic of returning to the original activity again when moisture is removed.
  • the concentration of nitrous oxide contained in exhaust gas discharged from factories and incineration facilities is 10% or less.
  • the concentration of nitrous oxide discharged from the operating room by the surplus anesthetic gas exclusion device may be as high as 3 to 70%.
  • the reaction when decomposing nitrous oxide contained in the anesthetic gas, the reaction usually involves 13 to 20% oxygen, and the reaction is performed under conditions that are severe for the decomposition catalyst.
  • the concentration of nitrous oxide to be decomposed is not particularly limited, but the reaction in which nitrous oxide decomposes into nitrogen and oxygen is an exothermic reaction.
  • the concentration of nitric oxide is preferably 3 to 50%, preferably 3 to 25%, more preferably 3 to 10%.
  • Space velocity is the amount of gas supplied per unit catalyst (SV: Space Velocity) may be in the range of 10hr -1 ⁇ 20000hr -1, preferably in the range of 100hr -1 ⁇ 10000hr -1.
  • the nitrous oxide decomposition catalyst of the present invention is a catalyst capable of decomposing a low concentration to a high concentration nitrous oxide.
  • the concentration of nitrous oxide contained in the surplus anesthetic gas discharged from the operating room is 70% or less, although it is somewhat diluted with compressed air, and is very high. This can be achieved by using a decomposition catalyst for nitrogen oxides.
  • the nitrous oxide decomposition catalyst of the present invention can recover its activity by activating regeneration even when it is deteriorated by the volatile anesthetic contained in the excess anesthetic gas. Moreover at a relatively low temperature can decompose nitrous oxide, less subject to deactivation due to water even when water coexists, it is possible to suppress the generation amount of the NO x to less than the allowable concentration, conventional cracking catalysts respect, it is possible to reduce the generation amount of the NO x to about 1 / 10-1 / 100 following levels.
  • the nitrous oxide decomposition catalyst of the present invention contains at least one noble metal selected from the group consisting of rhodium, ruthenium and palladium as an essential component, and is any one of the following (1) to (3) A catalyst can be used.
  • a catalyst comprising (a) at least one noble metal selected from the group consisting of rhodium, ruthenium and palladium on a carrier selected from silica or silica alumina.
  • the silica support includes (a) at least one noble metal selected from the group consisting of rhodium, ruthenium and palladium, (b) aluminum, and (c) at least one metal selected from the group consisting of zinc, iron and manganese. And a catalyst.
  • the support used for the catalyst of (1) is silica or silica alumina, and these supports are not particularly limited, but those having a surface area of about 50 to 300 m 2 / g can be used.
  • the carrier used for the catalyst of (2) is silica and is not particularly limited, but those having a surface area of about 50 to 300 m 2 / g can be used. Although there is no restriction
  • At least one metal selected from the group (c) consisting of zinc, iron and manganese is preferably contained in an amount of 0.1 to 5.0% by mass of the total catalyst mass, more preferably Is preferably contained in an amount of 0.2 to 1.0% by mass. Even if the metal selected from the group (c) is contained in an amount of 5.0% by mass or more based on the total mass of the catalyst, the effect may be saturated.
  • the aluminum supported on the silica support is preferably contained in an atomic ratio of at least 2 to at least one metal selected from the group (c) consisting of zinc, iron and manganese. Further, it is preferable that at least a part of aluminum forms a spinel crystalline composite oxide with at least one metal selected from the group (c), and the spinel crystalline composite oxide includes, for example, aluminum, zinc, iron And can be produced by firing a support on which at least one metal selected from the group consisting of manganese is supported.
  • a spinel structure is a structure found in an oxide having a chemical formula of XY 2 O 4 , belongs to a cubic system, and Al, Zn, Fe, and Mn are ZnAl 2 O 4 , FeAl 2 O 4 , and MnAl 2 O, respectively. It is known to form four spinel structures.
  • at least a part of aluminum is a part or all of at least one metal selected from the group (c) and a spinel-type crystalline composite oxide. It is considered that by forming, the effect of improving the resolution of nitrous oxide and reducing the amount of NO x generated is exhibited.
  • the carrier used for the catalyst of (3) is silica alumina and is not particularly limited, but those having a surface area of about 50 to 300 m 2 / g can be used.
  • the at least one metal selected from the group (d) consisting of magnesium, zinc, iron and manganese supported on the silica-alumina carrier is preferably contained in an amount of 0.1 to 5.0% by mass of the total catalyst mass, and more preferably Is preferably contained in an amount of 0.2 to 1.0% by mass. Even if the metal selected from the group (d) is contained in an amount of 5.0% by mass or more of the entire catalyst mass, the effect may be saturated.
  • the aluminum contained in the catalyst is preferably contained in an atomic ratio of at least 2 to at least one metal selected from the group (d) consisting of magnesium, zinc, iron and manganese. Further, it is preferable that at least a part of aluminum forms a spinel crystalline composite oxide with at least one metal selected from the group (d).
  • the spinel type crystalline composite oxide can be produced by supporting at least one metal selected from the group (d) on a silica alumina support and firing the support.
  • the at least one noble metal selected from the group (a) consisting of rhodium, ruthenium and palladium contained in the nitrous oxide decomposition catalyst of the present invention may be any of the above-mentioned catalysts (1) to (3).
  • the content is preferably 0.05 to 10% by mass, more preferably 0.1 to 6.0% by mass based on the total mass of the catalyst.
  • nitrous oxide decomposition catalyst of this invention is demonstrated.
  • Various production methods can be used for the nitrous oxide decomposition catalyst of the present invention.
  • methods such as (1) impregnation method, (2) coprecipitation method, and (3) kneading method can be used.
  • a method for producing the catalyst (2) using the impregnation method will be described, but it is needless to say that the present invention is not limited thereto.
  • the method of producing the catalyst of (2) using the impregnation method can include the following three steps. [1] A step of supporting (b) aluminum and (c) at least one metal selected from the group consisting of zinc, iron and manganese on a silica support. [2] A step of calcining the carrier obtained from step [1] at 400 to 900 ° C. [3] A step of (a) supporting at least one noble metal selected from the group consisting of rhodium, ruthenium and palladium on the calcined carrier obtained from the step [2].
  • step [1] an inorganic acid salt of aluminum and at least one metal inorganic acid salt selected from the group (c) consisting of zinc, iron and manganese (nitrate, hydrochloride, sulfate, etc.) Alternatively, impregnation with an organic acid salt (oxalate, acetate, etc.).
  • both the aluminum and the salt of at least one metal selected from the group (c) are nitrates.
  • the amount of aluminum and at least one metal selected from group (c) supported on the carrier is preferably such that aluminum is supported at an atomic ratio of at least 2 with respect to at least one metal selected from group (c).
  • the supported amount of at least one metal selected from the group (c) is 0.1 to 5.0% by mass of the entire catalyst mass.
  • the support is dried and further subjected to calcination step [2] to contain at least one metal selected from the group consisting of aluminum and group (c).
  • a carrier in which a part forms a spinel crystalline composite oxide with at least one metal selected from the group (c) consisting of zinc, iron and manganese can be obtained.
  • the drying temperature after step [1] is not particularly limited, but is preferably in the temperature range of 80 to 150 ° C, more preferably in the temperature range of 100 to 130 ° C.
  • the drying atmosphere is not particularly limited, but air is preferably used.
  • the drying time is not particularly limited, but when using the impregnation method, it may usually be about 2 to 4 hours.
  • the firing step [2] can be performed in a temperature range of 400 to 900 ° C., preferably 500 to 700 ° C.
  • the firing time is not particularly limited, but may be about 1 to 10 hours, preferably about 2 to 4 hours, and the firing temperature may be changed stepwise. Long-time firing may be saturated economically because the effect may be saturated, and short-time firing may be less effective.
  • baking can be performed using a baking furnace, a muffle furnace, etc., and any of nitrogen or air may be used as a distribution gas at this time.
  • At least a part of the aluminum forms a spinel crystalline composite oxide with at least one metal selected from the group (c) consisting of zinc, iron and manganese.
  • a salt of at least one noble metal selected from the group (a) consisting of rhodium, ruthenium and palladium As the salt of at least one noble metal selected from the group (a), an inorganic acid salt (nitrate, hydrochloride, sulfate, etc.) or an organic acid salt (oxalate, acetate, etc.) can be used. Preference is given to using the nitrate salt.
  • the step [3] is performed on the support obtained in the step [2] in which at least a part of aluminum forms a spinel crystalline complex oxide with at least one metal selected from the group (c). Although it is preferable, it may be performed simultaneously with the step [1]. In that case, the process [1] and the process [3] are performed at the same time, and then the process [2] is performed. At least a part of the aluminum is at least one metal selected from the group (c) and the spinel crystalline composite. It is preferable to form an oxide. In any case, it is preferable that the supported amount of at least one noble metal selected from the group (a) consisting of rhodium, ruthenium and palladium is 0.05 to 10% by mass based on the total mass of the catalyst. .
  • the catalyst precursor subjected to step [3] is dried under the same drying conditions as described above.
  • the dried catalyst precursor is preferably subjected to a reduction treatment, and a catalyst containing at least one noble metal selected from the group (a) having high activity can be obtained by the reduction treatment.
  • the reduction treatment can be performed by, for example, (1) a method of re-drying after hydrazine reduction and firing, or (2) a method of hydrogen reduction, and a method of hydrogen reduction is preferably used.
  • the reduction temperature is preferably 200 to 500 ° C., more preferably 300 to 400 ° C.
  • the reduction time is not particularly limited, the treatment can be performed in about 1 to 10 hours, preferably about 2 to 4 hours.
  • the dried catalyst precursor may be calcined in nitrogen or air without the reduction treatment (1) or (2).
  • the firing temperature at this time is preferably 200 to 500 ° C., more preferably 300 to 400 ° C.
  • the nitrous oxide decomposition method of the present invention includes the following four methods.
  • the nitrous oxide decomposition method (1) of the present invention is characterized in that a gas containing nitrous oxide is brought into contact with the catalyst at 200 to 600 ° C.
  • the nitrous oxide decomposition method (2) of the present invention is a catalyst in which at least one noble metal selected from the group consisting of rhodium, ruthenium and palladium is supported on a support made of silica or silica alumina. Yes, the gas containing nitrous oxide and the catalyst are brought into contact with each other at 200 to 600 ° C.
  • the supply of the gas containing nitrous oxide is stopped and 500 ° C. It is characterized by restarting the supply of gas containing nitrous oxide after heating to ⁇ 900 ° C. to activate and regenerate the catalyst.
  • the catalyst is silica and the support includes (a) at least one noble metal selected from the group consisting of rhodium, ruthenium and palladium, and (b) aluminum. And (c) a catalyst carrying at least one metal selected from the group consisting of zinc, iron and manganese, contacting the gas containing nitrous oxide with the catalyst at 200 to 600 ° C. for decomposition
  • the supply of the gas containing nitrous oxide is stopped and heated to 500 ° C. to 900 ° C., and the catalyst is activated and regenerated. The supply is resumed.
  • the catalyst is a silica alumina carrier, and (a) at least one noble metal selected from the group consisting of rhodium, ruthenium and palladium, and (D) A catalyst which carries at least one metal selected from the group consisting of magnesium, zinc, iron and manganese, which is brought into contact with the gas containing nitrous oxide at 200 to 600 ° C. for decomposition.
  • the supply of the gas containing nitrous oxide is stopped and heated to 500 ° C. to 900 ° C., and the catalyst is activated and regenerated. The supply is resumed.
  • the contact temperature between the nitrous oxide-containing gas and the decomposition catalyst is 200 to 600 ° C., preferably 300 to 500 ° C., more preferably 350 ° C. to 450 ° C. It is desirable to do.
  • the contact temperature is lower than 200 ° C., decomposition of nitrous oxide may not be sufficient, and when it is 600 ° C. or higher, the catalyst life tends to be short.
  • the catalyst bed system is not particularly limited, but a fixed bed can be employed.
  • the concentration of nitrous oxide contained in the exhaust gas discharged from factories and incineration facilities is usually 1000 ppm or less, but it is discharged by the surplus anesthetic gas exclusion device in the operating room.
  • the concentration of nitrous oxide is very high, about 8-50%.
  • 13 to 20% of oxygen is usually present in the excess anesthetic gas, it is a severe condition for the decomposition catalyst. If heat removal is possible and the temperature can be controlled, the concentration of nitrous oxide contacted with the cracking catalyst is not particularly limited.
  • nitrous oxide The concentration is preferably 50% or less, preferably 25% or less, and more preferably about 5%.
  • Space velocity is the amount of gas supplied per unit catalyst (Space Velocity) is preferably in the range of 10hr -1 ⁇ 20000hr -1, more preferably from 100 hr -1 ⁇ 10000 hr -1 is preferred.
  • the gas containing nitrous oxide may contain a volatile anesthetic, but the nitrous oxide decomposition catalyst of the present invention is not easily poisoned by the volatile anesthetic and is also poisoned by the volatile anesthetic. Even when the catalytic activity is reduced due to the above, by using the decomposition method of the present invention, the catalytic activity can be recovered and nitrous oxide can be decomposed over a long period of time. Therefore, when a decrease in the activity of the nitrous oxide decomposition catalyst is observed, the supply of the gas containing nitrous oxide is once stopped, the catalyst is activated to regenerate by calcination, and then the nitrous oxide is contained. The supply of gas can be resumed.
  • the calcination treatment for activating and regenerating the catalyst can be performed at a temperature of 500 to 900 ° C., preferably a decomposition catalyst whose activity is reduced at a temperature of 600 to 800 ° C., more preferably 650 to 750 ° C. .
  • an inert gas such as helium or nitrogen or air can be circulated through the catalyst layer, and oxygen may be contained in the inert gas. It is convenient and preferable to use air.
  • the firing treatment time is 10 minutes to 12 hours, preferably 20 minutes to 6 hours, more preferably about 30 minutes to 2 hours.
  • the catalyst supporting at least one noble metal selected from the group (a) consisting of rhodium, ruthenium and palladium
  • the catalyst is less susceptible to poisoning by volatile anesthetics and the activity of the catalyst is easily recovered. It is a catalyst containing ruthenium, and there is a tendency that the activity decreases in the order of rhodium and palladium. Therefore, it is desirable to use at least ruthenium as the noble metal component selected from the group (a). Further, after the baking treatment, a reduction treatment with hydrogen may be performed.
  • the catalyst used in the decomposition method (3) of the present invention comprises at least one metal selected from the group (c) consisting of zinc, iron, and manganese among the components supported on the silica support, in an amount of 0.1% of the total catalyst mass. It is preferably contained in an amount of ⁇ 5.0% by mass, more preferably 0.2-1.0% by mass. Even if the metal selected from the group (c) is contained in an amount of 5.0% by mass or more based on the total mass of the catalyst, the effect may be saturated.
  • the aluminum supported on the silica support is preferably contained in an atomic ratio of at least 2 to at least one metal selected from the group (c) consisting of zinc, iron and manganese. Further, it is preferable that at least a part of aluminum forms a spinel crystalline composite oxide with at least one metal selected from the group (c), and the spinel crystalline composite oxide includes, for example, aluminum, zinc, iron And can be produced by firing a support on which at least one metal selected from the group consisting of manganese is supported.
  • the catalyst used in the decomposition method (4) is a catalyst comprising at least one metal selected from the group (d) consisting of magnesium, zinc, iron and manganese supported on a silica-alumina carrier in an amount of 0.1 to The content is preferably 5.0% by mass, more preferably 0.2 to 1.0% by mass. Even if the metal selected from the group (d) is contained in an amount of 5.0% by mass or more of the entire catalyst mass, the effect may be saturated.
  • aluminum is contained in an atomic ratio of at least 2 with respect to at least one metal selected from the group (d) consisting of magnesium, zinc, iron and manganese. Further, it is preferable that at least a part of aluminum forms a spinel crystalline composite oxide with at least one metal selected from the group (d).
  • the spinel type crystalline composite oxide can be produced by supporting at least one metal selected from the group (d) on a silica alumina support and firing the support.
  • At least one noble metal selected from the group (a) consisting of rhodium, ruthenium and palladium contained in the catalyst used in the nitrous oxide decomposition method of the present invention is any of the decompositions (1) to (4) above Even when the method is used, it is preferably contained in an amount of 0.05 to 10% by mass, more preferably 0.1 to 6.0% by mass based on the total mass of the catalyst. Although it is possible to improve the catalytic activity at low temperature by increasing the amount of at least one noble metal selected from the group (a), it is not preferable to support 10% by mass or more in view of the cost of the catalyst, Further, if it is 0.05% by mass or less, sufficient nitrous oxide decomposition activity may not be obtained.
  • a catalyst for decomposing nitrous oxide made by Showa Denko KK, alumina carrier (manufactured by JGC Universal Co., Ltd.) with 5% rhodium and 1% zinc, granular, average particle size: 3 .2 mm
  • 2.12 g (4 ml) decomposition reactor nickel reaction tube, 1/2 inch diameter, catalyst layer height 57 mm
  • the nitrous oxide gas was decomposed while supplying a nitrous oxide (N 2 O) gas having a concentration of 100% by downflow to the decomposition reactor.
  • the flow rate was adjusted in a range of 20 to 2422 cc / min by a flow rate adjusting valve. Then, the linear velocity (LV: Linear Velocity) [m / min] and the space velocity (SV) [hr ⁇ 1 ] of the nitrous oxide gas supplied to the decomposition reactor at that time are measured, and The maximum value max [° C.] of the exothermic temperature (catalyst temperature) in the reaction vessel after decomposing the nitrogen oxide gas was measured with a temperature measuring device. Further, the amount of the NO X after decomposing nitrous oxide gas [ppm] was measured to determine the degradation rate of the nitrous oxide gas [%].
  • LV Linear Velocity
  • SV space velocity
  • Table 1 shows a summary of the measurement results. Moreover, the graph which put together the relationship between the linear velocity (LV) of nitrous oxide gas, the exothermic temperature in reaction container, and the decomposition rate of nitrous oxide gas from the measurement result of Table 1 is shown in FIG.
  • nitrous oxide has the same decomposition rate (98.7%) as that during heating while maintaining the heat generation temperature in the reaction vessel by the decomposition heat generated by the decomposition of nitrous oxide gas even after the heater is stopped. It turns out that the decomposition of the gas can be continued. For this reason, about 1 hour (hr) after the heater stopped, the supply of the nitrous oxide gas was stopped and the decomposition of the nitrous oxide gas was forcibly terminated. From this, it was found that the decomposition heat generated by the decomposition of the nitrous oxide gas can continue the decomposition of the nitrous oxide gas supplied thereafter without heating by the heater.
  • nitrous oxide by using energy generated by decomposition of nitrous oxide, it is possible to use nitrous oxide as energy friendly to the global environment. Further, since nitrous oxide is finally decomposed into nitrogen and oxygen as a decomposition gas, this decomposition gas can be utilized as a new resource. Furthermore, since nitrous oxide can also be industrially produced, its industrial utility value is very high in the present invention.
  • nitrous oxide is a stable gas at normal temperature and atmospheric pressure, and since it has low toxicity, it is highly safe and easy to handle.
  • a liquefied high-pressure gas filled in a high-pressure gas container it can be easily transported and stored before decomposition.
  • nitrous oxide has a low melting point (about ⁇ 90 ° C.) and does not freeze in outer space. Therefore, nitrous oxide does not stop its use on the earth, and other celestial bodies (such as the moon and Mars) and outer space (for example, It can also be used on a space station or spaceship.
  • nitrous oxide can be decomposed into nitrogen and oxygen, for example, in the space environment such as a space station and a spacecraft, and in the sea environment such as a submarine station and a submarine, energy required for space activities and underwater activities is obtained. It can be used not only as a supply source, but also as a supply source of respiratory gas necessary for life support.
  • oxygen obtained by decomposing nitrous oxide can be combined with an appropriate fuel such as hydrogen or methanol to be used for a fuel cell (primary cell), for example. Further, it can be combined with a battery (secondary battery) or the like.
  • SYMBOLS 1 Catalyst for nitrous oxide decomposition

Landscapes

  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Biomedical Technology (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Exhaust Gas Treatment By Means Of Catalyst (AREA)

Abstract

L'invention concerne un appareil de transport de chaleur et un procédé de transport de chaleur au moyen desquels de l'oxyde nitreux peut être utilisé comme source d'énergie respectueuse de l'environnement. L'appareil de l'invention comprend: un échangeur thermique côté absorption de chaleur (3) qui absorbe la chaleur par échange thermique avec l'extérieur lorsqu'un gaz d'oxyde nitreux (N2O) obtenu par expansion adiabatique de l'oxyde nitreux traverse l'intérieur de l'échangeur thermique (3); un réacteur de décomposition (2) dans lequel est disposé un catalyseur de décomposition (1) de l'oxyde nitreux, lequel catalyseur est utilisé pour décomposer le gaz d'oxyde nitreux lorsque ce dernier traverse l'intérieur du réacteur de décomposition; et un échangeur thermique côté dissipation de chaleur (4) qui dissipe la chaleur par échange thermique avec l'extérieur lorsqu'un gaz de décomposition (N2, O2) obtenu par décomposition du gaz d'oxyde nitreux dans le réacteur de décomposition (2) traverse l'intérieur de l'échangeur thermique (4).
PCT/JP2012/054346 2012-02-23 2012-02-23 Appareil de transport de chaleur, et procédé de transport de chaleur WO2013124998A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/JP2012/054346 WO2013124998A1 (fr) 2012-02-23 2012-02-23 Appareil de transport de chaleur, et procédé de transport de chaleur

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2012/054346 WO2013124998A1 (fr) 2012-02-23 2012-02-23 Appareil de transport de chaleur, et procédé de transport de chaleur

Publications (1)

Publication Number Publication Date
WO2013124998A1 true WO2013124998A1 (fr) 2013-08-29

Family

ID=49005220

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2012/054346 WO2013124998A1 (fr) 2012-02-23 2012-02-23 Appareil de transport de chaleur, et procédé de transport de chaleur

Country Status (1)

Country Link
WO (1) WO2013124998A1 (fr)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH054027A (ja) * 1991-06-28 1993-01-14 Asahi Chem Ind Co Ltd 排一酸化二窒素ガスの処理方法
JPH05285344A (ja) * 1992-04-06 1993-11-02 Osaka Gas Co Ltd 窒素酸化物含有ガスの処理方法
JP2002513907A (ja) * 1998-05-07 2002-05-14 クライオジェン インコーポレイテッド ジュール−トムソンプローブ用の予冷システム
JP2002172171A (ja) * 2000-09-27 2002-06-18 Showa Denko Kk 余剰麻酔ガスの処理方法及び処理装置
JP2005230795A (ja) * 2004-01-21 2005-09-02 Asahi Kasei Chemicals Corp 亜酸化窒素の分解方法およびその反応器
JP4232820B2 (ja) * 2006-12-06 2009-03-04 独立行政法人 宇宙航空研究開発機構 亜酸化窒素を用いたスラスタ装置

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH054027A (ja) * 1991-06-28 1993-01-14 Asahi Chem Ind Co Ltd 排一酸化二窒素ガスの処理方法
JPH05285344A (ja) * 1992-04-06 1993-11-02 Osaka Gas Co Ltd 窒素酸化物含有ガスの処理方法
JP2002513907A (ja) * 1998-05-07 2002-05-14 クライオジェン インコーポレイテッド ジュール−トムソンプローブ用の予冷システム
JP2002172171A (ja) * 2000-09-27 2002-06-18 Showa Denko Kk 余剰麻酔ガスの処理方法及び処理装置
JP2005230795A (ja) * 2004-01-21 2005-09-02 Asahi Kasei Chemicals Corp 亜酸化窒素の分解方法およびその反応器
JP4232820B2 (ja) * 2006-12-06 2009-03-04 独立行政法人 宇宙航空研究開発機構 亜酸化窒素を用いたスラスタ装置

Similar Documents

Publication Publication Date Title
JP5908059B2 (ja) 発電装置、発電方法、分解ガスボイラー及び分解ガスタービン
JP6706277B2 (ja) アンモニア分解装置
JP6261759B2 (ja) 内燃機関のｃｏ２回収装置
ES2938659T3 (es) Procedimiento e instalación para la fabricación de ácido nítrico
TW202035932A (zh) 熱利用系統及發熱裝置
WO2014073576A1 (fr) Catalyseur de décomposition oxydative de l'ammoniac, procédé de production d'hydrogène, et appareil de production d'hydrogène
US10787367B2 (en) Removal of gaseous NH3 from an NH3 reactor product stream
ES2940288T3 (es) Reducción de las emisiones de óxidos de nitrógeno durante el arranque de instalaciones para la fabricación de ácido nítrico
Jin et al. Catalytic combustion of methane over Pd/Ce–Zr oxides washcoated monolithic catalysts under oxygen lean conditions
JP6566662B2 (ja) アンモニア酸化分解触媒、並びにアンモニア酸化分解触媒を用いる水素製造方法及び水素製造装置
US20050025692A1 (en) Methods and apparatus for small-scale synthesis of ammonia
JP6076030B2 (ja) エネルギー取出装置
JP2013167421A (ja) 熱輸送装置及び熱輸送方法
JP2013167420A (ja) 熱輸送装置及び熱輸送方法
WO2013124998A1 (fr) Appareil de transport de chaleur, et procédé de transport de chaleur
WO2013125003A1 (fr) Appareil d'extraction d'énergie, et procédé d'extraction d'énergie
JP5891293B2 (ja) 熱輸送方法
WO2013125000A1 (fr) Appareil de transport de chaleur, et procédé de transport de chaleur
TW201341657A (zh) 發電裝置、發電方法、分解氣體鍋鑪及分解氣體渦輪機、熱輸送裝置及熱輸送方法
JP6447996B2 (ja) Ｎｉ基金属間化合物を含む触媒、その製造方法、および、それを用いた水素の製造方法
KR101842581B1 (ko) 자립형 셀프서스테이닝 방식의 열교환기타입 모듈형 리포머
US12013121B2 (en) Exhaust gas purification device for gas turbine engine
WO2023032427A1 (fr) Système et procédé de conversion de co2 en carburant
KR101985730B1 (ko) 암모니아 발생 및 방출 장치
JP6629699B2 (ja) 蓄熱システム

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12869006

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12869006

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP