US20140165380A1 - Method for fabricating exhaust gas decontamination reactor - Google Patents

Method for fabricating exhaust gas decontamination reactor Download PDF

Info

Publication number
US20140165380A1
US20140165380A1 US14/092,543 US201314092543A US2014165380A1 US 20140165380 A1 US20140165380 A1 US 20140165380A1 US 201314092543 A US201314092543 A US 201314092543A US 2014165380 A1 US2014165380 A1 US 2014165380A1
Authority
US
United States
Prior art keywords
exhaust gas
metal oxides
fabricating
reducing
gas decontamination
Prior art date
Legal status (The legal status 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 status listed.)
Abandoned
Application number
US14/092,543
Other languages
English (en)
Inventor
Shang-Hsiao WONG
Sheng-Shian WU
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
National Tsing Hua University NTHU
Original Assignee
National Tsing Hua University NTHU
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 National Tsing Hua University NTHU filed Critical National Tsing Hua University NTHU
Assigned to NATIONAL TSING HUA UNIVERSITY reassignment NATIONAL TSING HUA UNIVERSITY ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: WONG, SHANG-HSIAO, WU, SHENG-SHIAN
Publication of US20140165380A1 publication Critical patent/US20140165380A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/50—Catalysts, in general, characterised by their form or physical properties characterised by their shape or configuration
    • B01J35/56—Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional monoliths
    • 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
    • B01D53/32—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 by electrical effects other than those provided for in group B01D61/00
    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/002—Mixed oxides other than spinels, e.g. perovskite
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/83—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with rare earths or actinides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/89—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals
    • B01J23/8933—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals also combined with metals, or metal oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/894—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals also combined with metals, or metal oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with rare earths or actinides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
    • B01J35/33—Electric or magnetic properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/024—Multiple impregnation or coating
    • B01J37/0244—Coatings comprising several layers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
    • F01N13/08—Other arrangements or adaptations of exhaust conduits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
    • F01N13/16—Selection of particular materials
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/24—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
    • F01N3/28—Construction of catalytic reactors
    • F01N3/2803—Construction of catalytic reactors characterised by structure, by material or by manufacturing of catalyst support
    • F01N3/2825—Ceramics
    • F01N3/2828—Ceramic multi-channel monoliths, e.g. honeycombs
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2251/00—Reactants
    • B01D2251/20—Reductants
    • B01D2251/202—Hydrogen
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2251/00—Reactants
    • B01D2251/20—Reductants
    • B01D2251/206—Ammonium compounds
    • B01D2251/2062—Ammonia
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2251/00—Reactants
    • B01D2251/20—Reductants
    • B01D2251/208—Hydrocarbons
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2523/00—Constitutive chemical elements of heterogeneous catalysts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/08—Heat treatment
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2510/00—Surface coverings
    • F01N2510/06—Surface coverings for exhaust purification, e.g. catalytic reaction
    • 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
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making

Definitions

  • the present invention relates to an electrochemical-catalytic converter, particularly to a method for fabricating an exhaust gas decontamination pipe and an exhaust gas decontamination honeycombed structure.
  • the emission standard of motor vehicles has been advanced persistently. However, the continuously increasing motor vehicles still bring about more and more serious air pollution.
  • the engine thereof burns fuel and converts chemical energy into mechanical energy.
  • the burning process of fuel generates exhaust gases, including oxynitrides, carbon monoxide (CO), hydrocarbons (HC), and particulate matters, smoke, non-methane hydrocarbons (NMHC), and methane (CH 4 ), which would form photochemical smog, deplete ozone, enhance the greenhouse effect, cause acid rain, damage the ecological environment and endanger human health.
  • the capability of carbon monoxide to combine with hemoglobin to form carboxyhemoglobin (COHb) is 300 times higher than the capability of oxygen to combine with hemoglobin to form oxyhemoglobin (HbO 2 ). Therefore, too high a concentration of carbon monoxide would degrade the capability of hemoglobin to transport oxygen.
  • Oxynitrides are generated by the combination of nitrogen and oxygen and mainly in form of nitrogen monoxide (NO) and nitrogen dioxide (NO 2 ). Oxynitrides are also likely to combine with hemoglobin and would impair the breathing and circulating functions. Hydrocarbons can irritate the respiratory system even at a lower concentration and will affect the central nervous system at higher concentration.
  • a catalytic oxidizing converter is installed in the exhaust pipe of a diesel engine vehicle to catalytically convert carbon monoxide (CO) and hydrocarbons (HCs), and an EGR (Exhaust Gas Recirculation) system or a cylinder water-spray apparatus is used to eliminate oxynitrides (NO x ).
  • EGR Exhaust Gas Recirculation
  • a cylinder water-spray apparatus is used to eliminate oxynitrides (NO x ).
  • SCR Selective Catalytic Reduction
  • ammonia (NH 3 ) gas or an aqueous urea (CO(NH 2 ) 2 ) solution is used as a reactant.
  • the aqueous urea solution is sprayed into the exhaust pipe via nozzles and decomposed into ammonia gas. Then, the ammonia gas reacts with oxynitrides (NO x ) to generate products—nitrogen and water.
  • NO x oxynitrides
  • ammonia gas is poisonous, hard to store and likely to leak. Further, incomplete reaction of ammonia will cause secondary pollution.
  • the SCR system is bulky and has to cooperate with precision sensors.
  • a U.S. Pat. No. 5,401,372 disclosed an “Electrochemical Catalytic Reduction Cell for the Reduction of NO x in an O 2 -Containing Exhaust Emission”, which is dedicated to removing oxynitrides, wherein an electrocatalytic reducing reaction and a vanadium pentaoxide (V 2 O 5 ) catalyst convert oxynitrides into nitrogen.
  • V 2 O 5 vanadium pentaoxide
  • a U.S. patent application Ser. No. 13/037,693 disclosed an “Electrochemical-Catalytic Converter for Exhaust Emission Control”, which can eliminate oxynitrides (NO x ), carbon monoxide (CO), hydrocarbons (HC), and particulate matters (PM) in exhaust gas, and which comprises a battery module, wherein oxynitrides are electrocatalytically decomposed into nitrogen and oxygen, and wherein carbon monoxide, hydrocarbons, and particulate matters are converted into water and carbon dioxide by an oxidizing catalyst. Therefore, the prior art can eliminates multiple harmful gases simultaneously.
  • Electrochemical-Catalytic Converter is hard to fabricate into a compact structure for vehicle application. Therefore, the prior art still has room to improve.
  • the primary objective of the present invention is solve the problem that the conventional electrochemical-catalytic converter requires an additional reducing-gas system for generating electromotive force, which makes the fabrication cost increase, the structure likely to damage, and the volume hard to decrease.
  • the present invention proposes a method for fabricating an exhaust gas decontamination reactor, which is an exhaust gas decontamination pipe or an exhaust gas decontamination honeycombed structure.
  • the method for fabricating an exhaust gas decontamination pipe comprises the following steps:
  • a pipe made of a solid-state oxide and including an internal channel, an inner wall surface surrounding the internal channel, and an outer wall surface far away from the inner wall surface;
  • the method for fabricating a honeycombed structure comprises the following steps:
  • honeycombed structure made of a solid-state oxide and including a plurality of tubes and a plurality of separation walls between the tubes;
  • green cathode layers which contain a cathode material, on first inner wall surfaces of the first passages, and undertaking a first sintering process to convert the green cathode layers into cathode layers on the first inner wall surfaces;
  • green anode layers which contain an anode material, on second inner wall surfaces of the second passages, and undertaking a second sintering process to convert the green anode layers into anode layers on the second inner wall surfaces, whereby the separation walls are between the anode layers and the cathode layers;
  • the exhaust gas decontamination reactor fabricated according to the present invention can merely use the cathode layers to decontaminate exhaust gas without using any additional reducing-gas system. Therefore, the method of the present invention is able to reduce the fabrication cost, and the exhaust gas decontamination reactor fabricated by the present invention is less likely to be damaged.
  • the present invention needn't arrange a reducing-gas system in the exhaust gas decontamination reactor and thus can obviously decrease the volume of the exhaust gas decontamination reactor. Therefore, the exhaust gas decontamination reactor fabricated according to the present invention can be arranged inside the exhaust pipe of a vehicle engine to decontaminate the harmful matters generated by oxygen-enriched combustion and reduce the air pollution.
  • FIGS. 1A-1D are diagrams schematically showing the process of fabricating an exhaust gas decontamination pipe according to a first embodiment of the present invention.
  • FIGS. 2A-2D are diagrams schematically showing the process of fabricating an exhaust gas decontamination honeycombed structure according to a second embodiment of the present invention.
  • the present invention provides a method for fabricating an exhaust gas decontamination reactor, which is an exhaust gas decontamination pipe or an exhaust gas decontamination honeycombed structure.
  • an exhaust gas decontamination reactor which is an exhaust gas decontamination pipe or an exhaust gas decontamination honeycombed structure.
  • a first embodiment and a second embodiment are respectively used to demonstrate a method for fabricating an exhaust gas decontamination pipe and a method for fabricating an exhaust gas decontamination honeycombed structure.
  • FIGS. 1A-1D diagrams schematically showing the process of fabricating an exhaust gas decontamination pipe according to a first embodiment of the present invention.
  • the method for fabricating an exhaust gas decontamination pipe comprises Steps 1 - 4 .
  • Step 1 provide a pipe 10 made of a solid-state oxide, as shown in FIG. 1A .
  • the solid-state oxide is a fluoride metal oxide or a perovskite metal oxide, such as a fluorite YSZ (yttria-stabilized zirconia), a stabilized zirconia, a fluorite GDC (gadolinia-doped ceria), a dopedceria, a perovskite LSGM (strontium/magnesium-doped lanthanum gallate), or a doped lanthanum gallate.
  • the pipe 10 is made of zirconia.
  • the pipe 10 includes an internal channel 11 , a first opening 14 , a second opening 15 , an inner wall surface 12 , and an outer wall surface 13 .
  • the internal channel 11 is between the first opening 114 and the second opening 15 and interconnects the first opening 14 and the second opening 15 .
  • the inner wall surface 12 surrounds the internal channel 11 .
  • the outer wall surface 13 is far away from the inner wall surface 12 .
  • Step 2 coat a green cathode layer, which contains a cathode material, on the outer wall surface 13 , and undertake a first sintering process to form a cathode layer 20 on the outer wall surface 13 , as shown in FIG. 1B .
  • the cathode material is selected from a group consisting of perovskite metal oxides, fluorite metal oxides, metal-containing perovskite metal oxides, and metal-containing fluorite metal oxides.
  • the cathode layer is made of a perovskite lanthanum strontium cobalt copper oxide, a lanthanum strontium manganese copper oxide, a combination of a lanthanum strontium cobalt copper oxide and a gadolinia-doped ceria; a combination of a lanthanum strontium manganese copper oxide and a gadolinia-doped ceria, a silver-containing lanthanum strontium cobalt copper oxide, a silver-containing lanthanum strontium manganese copper oxide, a combination of a silver-containing lanthanum strontium cobalt copper oxide and a gadolinia-doped ceria, or a combination of a silver-containing lanthanum strontium manganese copper oxide and a gadolinia-doped ceria.
  • the first sintering process is to degrease the cathode material and sinter the cathode
  • the green cathode layer is exemplified by one containing a combination of a lanthanum strontium manganese copper oxide and a gadolinia-doped ceria.
  • a combination of a lanthanum strontium manganese copper oxide and a gadolinia-doped ceria Firstly, enclose the first opening 14 and the second opening 15 with adhesive tapes. Next, coat a fluorite gadolinia-doped ceria on the outer wall surface 12 with a dipping method. Next, take off the adhesive tapes, and dry the pipe 10 in an oven at a temperature of 50° C. for 6 hours. Next, heat the pipe 10 at a temperature rising speed of 5° C./min to a temperature of 600° C., and soak the pipe 10 at 600° C. for 2 hours.
  • the following heating processes and cooling processes will be undertaken at the speed of 5° C./min also.
  • heat the pipe 10 to a temperature of 900° C., and soak the pipe 10 at 900° C. for 2 hours.
  • heat the pipe 10 to a temperature of 1200° C., and soak the pipe 10 at 1200° C. for 4 hours.
  • take off the adhesive tapes and dry the pipe 10 in an oven at a temperature of 50° C. for 6 hours.
  • Step 3 coat a green anode layer, which contains an anode material, on the inner wall surface 12 , and undertake a second sintering process to form an anode layer 30 on the inner wall surface 12 , as shown in FIG. 1C .
  • the anode material is selected from a group consisting of fluorite metal oxides, perovskite metal oxides, metal-containing fluorite metal oxides, and metal-containing perovskite metal oxides.
  • the anode material is a nickel-containing yttria-stabilized zirconia (Ni—YSZ cermet).
  • the green anode layer is exemplified by one containing Ni—YSZ cermet.
  • pour a slurry made of the anode material into the pipe 10 along the inner wall surface 12 and let the residual slurry slip away spontaneously, and then air-dry the slurry.
  • undertake a second sintering process Beforehand, dry the pipe 10 in an oven at a temperature of 50° C. for 6 hours. Then, undertake heat treatments at a temperate rising speed of 5° C./min. Heat the pipe 10 to a temperature of 300° C., and soak the pipe 10 at 300° C. for 2 hours. Next, heat the pipe 10 to a temperature of 600° C., and soak the pipe 10 at 600° C.
  • the second sintering process is the same as that of the first sintering process and will not repeat herein.
  • the second sintering process is different from the first sintering process in that nickel oxide needs to be reduced into nickel metal. Therefore, the green anode layer together with the pipe 10 is placed in a quartz tube for a reducing heat treatment.
  • the quartz tube is filled with hydrogen, heated at a temperature-rising speed of 5° C./min to a temperature of 400° C., and soaked at the temperature of 400° C. for 8 hours to reduce the combination of nickel oxide and the Ni—YSZ cermet into nickel metal and the Ni—YSZ cermet. Thereby is completed the anode layer 30 .
  • Step 4 provide a reducing environment 111 for the internal channel 11 , and seal the pipe 10 to enclose the reducing environment 111 and complete the exhaust gas decontamination pipe, as shown in FIG. 1D .
  • a reducing agent 112 is filled into the internal channel 11 to form the reducing environment 111 .
  • the reducing agent 112 may be a solid-state reducing agent (such as graphite powder or carbon black), a liquid reducing agent (such as aqueous ammonia solution), or a gaseous reducing agent (such as methane or hydrogen).
  • the reducing agent 112 is enclosed inside the internal channel 11 by sealing elements 113 to form the reducing environment 111 .
  • the sealing elements 113 are made of a heat-resistant ceramic putty having a thermal expansion coefficient near that of the pipe 10 .
  • the sealing element 113 normally contains aluminum oxides and silicon oxides.
  • the internal channel 11 is not filled with the reducing agent 112 but directly sealed by the sealing elements 113 , and the air pressure inside the internal 11 is lowered to below 1 atm, e.g. a vacuum state, whereby is also formed the reducing environment 111 .
  • FIGS. 2A-2D diagrams schematically showing the process of fabricating an exhaust gas decontamination honeycombed structure according to a second embodiment of the present invention.
  • the method for fabricating an exhaust gas decontamination honeycombed structure comprises Steps A-E.
  • the honeycombed structure 50 includes a plurality of tubes 51 and a plurality of separation walls 52 between each two tubes 51 , as shown in FIG. 2A .
  • the tubes 51 are separated by the separation walls 52 and arranged together.
  • the tubes 51 have square sections.
  • the present invention does not constrain that the sections of the tubes 51 must be square.
  • the tubes 51 may have circular or hexagonal sections, which are closely arranged to form a compact structure.
  • Step B define in the tubes 51 a plurality of first passages 511 allowing an exhaust gas 80 (shown in FIG. 2D ) to pass and a plurality of second passages 513 to be sealed later.
  • Each first passage 511 is adjacent to several second passages 513 .
  • the first passages 511 and the second passages 513 are alternately arranged to make each first passage 511 surrounded by four second passages 513 .
  • the present invention is not limited by the second embodiment.
  • Step C coat a green cathode layer containing a cathode material on a first inner wall surface 512 of each first passage 511 , and undertake a first sintering process to convert the green cathode layer into a cathode layer 60 on the first inner wall surface 512 , as shown in FIG. 2B .
  • Step C of the second embodiment is characterized in that the second passages 513 are sealed with silicone pads before the green cathode layers are coated on the first inner wall surfaces 512 .
  • the method to coat the green cathode layer and the first sintering process are the same as those in Step 2 and will not repeat herein. Thereby is obtained the cathode layer 60 in Step C.
  • Step D coat a green anode layer containing an anode material on a second inner wall surface 514 of the second passage 513 , and undertake a second sintering process to convert the green anode layer into an anode layer 70 on the second inner wall surface 514 , as shown in FIG. 2C .
  • the separation walls 52 are between the anode layers 70 and the cathode layers 60 .
  • Step D of the second embodiment is characterized in that the silicone pads sealing the second passages 513 are removed, and that the first passages 511 are sealed with silicone pads before the anode material is coated on the second inner wall surface 514 with a dipping method. Then, take off the silicone pads from the first passages 511 , and undertake the same second sintering process and reducing process as that used in Step 3 to convert the green anode layer into the anode layer 70 on the second inner wall surface 514 .
  • Step E provide reducing environments 515 for the second passages 513 , and seal the second passages 513 to enclose the reducing environments 515 and complete the exhaust gas decontamination honeycombed structure.
  • the reducing agents 516 , the sealing elements 517 and the method to form the reducing environments 515 are similar to those used in Step 4 .
  • Step E is different from Step 4 in that the reducing environments 515 are formed in the second passages 513 , and that the exhaust gas 80 flows through the first passages 511 , and that the separation walls 512 are formed between the first passages 511 and the second passages 513 .
  • the reducing environment 515 , the anode layer 70 , the separation wall 52 and the cathode layer 60 are sequentially formed from the second passage 513 to the first passage 511 . Then, the surfaces of the cathode layers 60 function as reaction sites to undertake a catalytic decomposition reaction of oxynitrides and decontaminate the exhaust gas 80 .
  • the exhaust gas decontamination pipe and honeycombed structure fabricated according to the present invention can merely use the cathode layers to decontaminate exhaust gas without using any additional reducing-gas system. Therefore, the method of the present invention is able to reduce the fabrication cost, and the exhaust gas decontamination reactor fabricated by the present invention is less likely to be damaged. As the present invention needn't arrange a reducing-gas system in the exhaust gas decontamination reactor, the present invention can obviously decrease the volume of the exhaust gas decontamination reactor. Therefore, the exhaust gas decontamination reactor fabricated according to the present invention can be arranged inside the exhaust pipe of a vehicle engine to decontaminate the harmful matters generated by oxygen-enriched combustion and reduce the air pollution.
  • the present invention possesses utility, novelty and non-obviousness and meets the condition for a patent.
  • the Inventors file the application for a patent. It is appreciated if the patent is approved fast.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Environmental & Geological Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Biomedical Technology (AREA)
  • Toxicology (AREA)
  • Exhaust Gas After Treatment (AREA)
  • Exhaust Gas Treatment By Means Of Catalyst (AREA)
  • Catalysts (AREA)
US14/092,543 2012-12-18 2013-11-27 Method for fabricating exhaust gas decontamination reactor Abandoned US20140165380A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
TW101148109 2012-12-18
TW101148109A TWI491436B (zh) 2012-12-18 2012-12-18 Production method of exhaust gas purifying reactor

Publications (1)

Publication Number Publication Date
US20140165380A1 true US20140165380A1 (en) 2014-06-19

Family

ID=50900825

Family Applications (1)

Application Number Title Priority Date Filing Date
US14/092,543 Abandoned US20140165380A1 (en) 2012-12-18 2013-11-27 Method for fabricating exhaust gas decontamination reactor

Country Status (3)

Country Link
US (1) US20140165380A1 (zh)
CN (1) CN103861453B (zh)
TW (1) TWI491436B (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114570172A (zh) * 2022-03-03 2022-06-03 张震渝 一种火电厂废气处理设备及处理工艺

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109772165B (zh) * 2018-12-14 2021-09-14 深圳大学 一种尾气净化反应器及其制备方法与尾气净化反应电堆

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1145588C (zh) * 1999-05-06 2004-04-14 科学技术振兴事业团 微量有害物质的氧化分解装置
GB0502227D0 (en) * 2005-02-03 2005-03-09 Thermal Energy Systems Ltd Gas separation and compresssion device
JP2009125622A (ja) * 2007-11-20 2009-06-11 Toyota Industries Corp 排気ガスの浄化装置
JP4803400B2 (ja) * 2008-03-27 2011-10-26 三菱自動車工業株式会社 内燃機関の排気浄化装置
TWI414343B (zh) * 2010-10-29 2013-11-11 Nat Univ Tsing Hua An electrochemical catalyst converter for controlling exhaust emissions

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114570172A (zh) * 2022-03-03 2022-06-03 张震渝 一种火电厂废气处理设备及处理工艺

Also Published As

Publication number Publication date
CN103861453B (zh) 2015-11-04
TWI491436B (zh) 2015-07-11
TW201424827A (zh) 2014-07-01
CN103861453A (zh) 2014-06-18

Similar Documents

Publication Publication Date Title
US20140166477A1 (en) Multilayer-structured exhaust gas decontamination reactor and method for fabricating the same
US8647482B2 (en) Electrochemical-catalytic converter for exhaust emission control
EP2591843A1 (en) Electro-catalytic tube for exhaust emissions control
TWI390104B (zh) 控制廢氣排放並發電的熱活電化學暨觸媒轉化器
KR101562289B1 (ko) 배기 배출물 제어를 위한 전기적 촉매 허니컴
TWM454870U (zh) 多層排列之廢氣淨化反應器
US20140165380A1 (en) Method for fabricating exhaust gas decontamination reactor
US20180008931A1 (en) Electro-catalytic honeycomb for exhaust emissions control and manufacturing method thereof
Huang et al. Kinetic behaviors of high concentration NOx removal from simulated lean-burn engine exhaust via electrochemical-catalytic cells
JP5655502B2 (ja) ガス分解素子、発電装置及びガス分解方法
US9028764B2 (en) Electro-catalytic honeycomb for exhaust emissions control
US10266956B1 (en) Method for manufacturing electro-catalytic honeycomb for controlling exhaust emissions
EP2724768B1 (en) Electro-catalytic honeycomb for exhaust emissions control
JP5787269B2 (ja) ガス分解素子、発電装置及びガス分解方法
JP5545227B2 (ja) ガス分解装置及び発電装置
JP5703762B2 (ja) ガス分解装置及び発電装置
JP2012157847A (ja) ガス分解装置及び発電装置
JP2014155923A (ja) ガス分解装置及び発電装置

Legal Events

Date Code Title Description
AS Assignment

Owner name: NATIONAL TSING HUA UNIVERSITY, TAIWAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:WONG, SHANG-HSIAO;WU, SHENG-SHIAN;REEL/FRAME:031707/0236

Effective date: 20121224

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION