CN116272758A - Sliding arc plasma reactor and method for efficiently converting methane by plasma - Google Patents
Sliding arc plasma reactor and method for efficiently converting methane by plasma Download PDFInfo
- Publication number
- CN116272758A CN116272758A CN202111567218.1A CN202111567218A CN116272758A CN 116272758 A CN116272758 A CN 116272758A CN 202111567218 A CN202111567218 A CN 202111567218A CN 116272758 A CN116272758 A CN 116272758A
- Authority
- CN
- China
- Prior art keywords
- sliding arc
- arc plasma
- plasma reactor
- reactor
- tubular electrode
- 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.)
- Pending
Links
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 title claims abstract description 224
- 238000000034 method Methods 0.000 title claims abstract description 49
- 238000006243 chemical reaction Methods 0.000 claims abstract description 93
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 15
- 239000007789 gas Substances 0.000 claims description 119
- 239000003054 catalyst Substances 0.000 claims description 49
- 239000012495 reaction gas Substances 0.000 claims description 31
- 239000000463 material Substances 0.000 claims description 27
- 230000007246 mechanism Effects 0.000 claims description 20
- 239000004020 conductor Substances 0.000 claims description 15
- 239000011810 insulating material Substances 0.000 claims description 10
- 229910000990 Ni alloy Inorganic materials 0.000 claims description 8
- 239000010935 stainless steel Substances 0.000 claims description 6
- 229910001220 stainless steel Inorganic materials 0.000 claims description 6
- 229910045601 alloy Inorganic materials 0.000 claims description 4
- 239000000956 alloy Substances 0.000 claims description 4
- NGXHCVZLMAKFAG-UHFFFAOYSA-N cobalt copper nickel Chemical compound [Ni][Co][Cu][Cu] NGXHCVZLMAKFAG-UHFFFAOYSA-N 0.000 claims description 4
- 229910000881 Cu alloy Inorganic materials 0.000 claims description 3
- PFNCLDWLINRYCV-UHFFFAOYSA-N [Cd].[Ni].[Co] Chemical compound [Cd].[Ni].[Co] PFNCLDWLINRYCV-UHFFFAOYSA-N 0.000 claims description 3
- ZGDWHDKHJKZZIQ-UHFFFAOYSA-N cobalt nickel Chemical compound [Co].[Ni].[Ni].[Ni] ZGDWHDKHJKZZIQ-UHFFFAOYSA-N 0.000 claims description 3
- YOCUPQPZWBBYIX-UHFFFAOYSA-N copper nickel Chemical compound [Ni].[Cu] YOCUPQPZWBBYIX-UHFFFAOYSA-N 0.000 claims description 3
- 229910000636 Ce alloy Inorganic materials 0.000 claims description 2
- IADRPEYPEFONML-UHFFFAOYSA-N [Ce].[W] Chemical compound [Ce].[W] IADRPEYPEFONML-UHFFFAOYSA-N 0.000 claims description 2
- SZMZREIADCOWQA-UHFFFAOYSA-N chromium cobalt nickel Chemical compound [Cr].[Co].[Ni] SZMZREIADCOWQA-UHFFFAOYSA-N 0.000 claims description 2
- 229910002804 graphite Inorganic materials 0.000 claims description 2
- 239000010439 graphite Substances 0.000 claims description 2
- 239000007769 metal material Substances 0.000 claims description 2
- 229910000623 nickel–chromium alloy Inorganic materials 0.000 claims 1
- 229910052799 carbon Inorganic materials 0.000 abstract description 18
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 abstract description 11
- 239000005977 Ethylene Substances 0.000 abstract description 11
- 150000001336 alkenes Chemical class 0.000 abstract description 10
- 238000004519 manufacturing process Methods 0.000 abstract description 8
- 239000000126 substance Substances 0.000 abstract description 7
- JRZJOMJEPLMPRA-UHFFFAOYSA-N olefin Natural products CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 abstract description 6
- 238000005265 energy consumption Methods 0.000 abstract description 5
- 230000008021 deposition Effects 0.000 abstract description 4
- 238000004880 explosion Methods 0.000 abstract description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 30
- 239000000047 product Substances 0.000 description 30
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 26
- 239000001257 hydrogen Substances 0.000 description 26
- 229910052739 hydrogen Inorganic materials 0.000 description 26
- 229930195733 hydrocarbon Natural products 0.000 description 16
- 150000002430 hydrocarbons Chemical class 0.000 description 15
- 229910052757 nitrogen Inorganic materials 0.000 description 15
- 238000007599 discharging Methods 0.000 description 14
- 239000004215 Carbon black (E152) Substances 0.000 description 13
- HSFWRNGVRCDJHI-UHFFFAOYSA-N alpha-acetylene Natural products C#C HSFWRNGVRCDJHI-UHFFFAOYSA-N 0.000 description 13
- 125000002534 ethynyl group Chemical group [H]C#C* 0.000 description 13
- OTMSDBZUPAUEDD-UHFFFAOYSA-N Ethane Chemical compound CC OTMSDBZUPAUEDD-UHFFFAOYSA-N 0.000 description 10
- 230000000052 comparative effect Effects 0.000 description 10
- 239000000376 reactant Substances 0.000 description 10
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 9
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 8
- 238000005516 engineering process Methods 0.000 description 8
- 239000001301 oxygen Substances 0.000 description 8
- 229910052760 oxygen Inorganic materials 0.000 description 8
- 230000008569 process Effects 0.000 description 7
- 230000009467 reduction Effects 0.000 description 6
- 238000005336 cracking Methods 0.000 description 5
- KDLHZDBZIXYQEI-UHFFFAOYSA-N palladium Substances [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 5
- 239000002994 raw material Substances 0.000 description 5
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 4
- 229910021193 La 2 O 3 Inorganic materials 0.000 description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 239000000919 ceramic Substances 0.000 description 4
- 230000008878 coupling Effects 0.000 description 4
- 238000010168 coupling process Methods 0.000 description 4
- 238000005859 coupling reaction Methods 0.000 description 4
- 238000009826 distribution Methods 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- XTVVROIMIGLXTD-UHFFFAOYSA-N copper(II) nitrate Chemical compound [Cu+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O XTVVROIMIGLXTD-UHFFFAOYSA-N 0.000 description 3
- 238000010891 electric arc Methods 0.000 description 3
- 238000011835 investigation Methods 0.000 description 3
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 3
- GPNDARIEYHPYAY-UHFFFAOYSA-N palladium(ii) nitrate Chemical compound [Pd+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O GPNDARIEYHPYAY-UHFFFAOYSA-N 0.000 description 3
- 238000002407 reforming Methods 0.000 description 3
- 239000002253 acid Substances 0.000 description 2
- 229910002092 carbon dioxide Inorganic materials 0.000 description 2
- 239000001569 carbon dioxide Substances 0.000 description 2
- 229910002091 carbon monoxide Inorganic materials 0.000 description 2
- 239000008367 deionised water Substances 0.000 description 2
- 229910021641 deionized water Inorganic materials 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- -1 ethane and the like Chemical class 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000005984 hydrogenation reaction Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229910000510 noble metal Inorganic materials 0.000 description 2
- 229910052763 palladium Inorganic materials 0.000 description 2
- 239000008188 pellet Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 239000010453 quartz Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 239000010963 304 stainless steel Substances 0.000 description 1
- 229910000589 SAE 304 stainless steel Inorganic materials 0.000 description 1
- 229910010413 TiO 2 Inorganic materials 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 150000001335 aliphatic alkanes Chemical class 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 239000006229 carbon black Substances 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000003889 chemical engineering Methods 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 239000010431 corundum Substances 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 230000001808 coupling effect Effects 0.000 description 1
- 238000005235 decoking Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000005431 greenhouse gas Substances 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000005470 impregnation Methods 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 229910001120 nichrome Inorganic materials 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 238000010926 purge Methods 0.000 description 1
- 238000000197 pyrolysis Methods 0.000 description 1
- 238000002390 rotary evaporation Methods 0.000 description 1
- 239000005341 toughened glass Substances 0.000 description 1
Images
Classifications
-
- 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
- B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J19/08—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor
- B01J19/087—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor employing electric or magnetic energy
- B01J19/088—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor employing electric or magnetic energy giving rise to electric discharges
-
- 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
- B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J19/0053—Details of the reactor
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2/00—Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms
- C07C2/76—Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by condensation of hydrocarbons with partial elimination of hydrogen
- C07C2/82—Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by condensation of hydrocarbons with partial elimination of hydrogen oxidative coupling
- C07C2/84—Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by condensation of hydrocarbons with partial elimination of hydrogen oxidative coupling catalytic
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2523/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group C07C2521/00
- C07C2523/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group C07C2521/00 of the iron group metals or copper
- C07C2523/89—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group C07C2521/00 of the iron group metals or copper combined with noble metals
-
- 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
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/36—Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Toxicology (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to the field of energy and chemical industry, and discloses a sliding arc plasma reactor and a method for efficiently converting methane by plasma, wherein the reactor comprises a first reactor inlet (11), a second reactor inlet (12), a tubular electrode sliding arc generator, a lower reaction zone (4) and a product outlet (5), and the tubular electrode sliding arc generator comprises a first gas nozzle (21), a second gas nozzle (22), a tubular electrode (3) and a base (6); at least 2 tubular electrodes (3) which are symmetrically distributed are arranged on the base (6). The sliding arc plasma reactor provided by the invention can obviously improve the conversion rate of methane, reduce energy consumption and improve the selectivity of ethylene in a product when methane conversion reaction is carried outSignificantly reduces carbon deposition, and compared with the traditional process for preparing olefin by methane, has no CO 2 The production is safe and environment-friendly, and the explosion risk is avoided.
Description
Technical Field
The invention relates to the field of energy and chemical industry, in particular to a sliding arc plasma reactor and a method for efficiently converting methane by using plasma.
Background
In the 80 s of the last century, china gradually began to study the plasma methane conversion technology.
CN1360008A, university of Tianjin discloses a process for preparing gasoline by converting methane and carbon dioxide using plasma. The method adds CO 2 As another reactant and the main product is gasoline.
CN1552680a discloses a method for preparing acetylene by thermal plasma cracking of methane-containing gas, which mainly adopts methane as a raw material and acetylene as a main byproduct, and the patent is patented by the end of 2012.
A series of patent technologies (CN 210367505U, CN109294284A, CN106478332A, CN 101921163A) for cracking methane by plasma are disclosed by southwest chemical engineering institute, and are developed mainly aiming at the process of preparing carbon black or acetylene and hydrogen by converting methane by plasma, and the design and optimization of the process are more focused.
The plasma cracking coal-to-acetylene process (CN 203582763U, CN102068953A, CN101734620A, CN101550057A, CN101734995A, CN 1613839A) is developed by the university of Qinghua, the university of Tai-Chi-Ji-shi, and the working gas is hydrogen, and mainly uses coal as a raw material and is used for preparing acetylene and hydrogen in an auxiliary way.
The method of on-line decoking of plasma is developed mainly at Zhejiang university (CN 104056828A, CN 104056829A), CO can be introduced 2 Or H 2 And removing carbon on the surface of the electrode. A rotating arc plasma cracking methane to acetylene (CN 103333044A, CN101844744 a) was also developed, with the working gas rotating into the discharge gap, while the outside was driven with a magnetic field, with millisecond cracking.
The analysis and summary of foreign literature patent shows that hydrocarbon products formed by converting methane by plasma are mainly divided into two types, one type is mainly composed of alkanes such as ethane and the like, and the other type is mainly composed of acetylene.
Other researchers have found that the product distribution can be adjusted by varying the inlet flow or incorporating inert gases. The technology has been industrialized abroad, and comprises four processes: HUELS method, AVCO method, du Pont method and Romania method.
According to literature comparison, the method for generating acetylene by utilizing high-temperature pyrolysis natural gas generated by electric arc has low electric energy utilization rate, and about power consumption 13900kWh is consumed for producing 1 ton of acetylene, which accounts for more than 50%, so that the aim of saving energy and reducing consumption is achieved by changing the structure of the reactor, and the method is one of the key points of innovation in foreign patent literature.
Based on the technology, a series of 'warm' plasma technology and 'cold' plasma technology are developed gradually, the energy consumption is reduced by changing the energy generation form, and a catalyst is added for coupling action, so that methane is directionally converted into a target product. The process is currently under investigation.
Thomas Hammer et al (Plasma Catalytic Hybrid Reforming of Methane [ M)]Utilization of Greenhouse gas. American Chemical society 2003:292-301.) ceramic pellets loaded with Ni using ceramic tubes as the blocking mediumAs a catalyst, CH was carried out 4 :H 2 Dielectric barrier discharge research of O mixture system, methane conversion rate of 7.9% without catalyst at 600 ℃ and product C 2 H 6 、C 3 H 8 、C 2 H 4 Yields of 4.1%, 0.73%, 0.71%, respectively; after adding Ni-loaded ceramic pellets, H 2 The conversion rate of O is increased, and the product is mainly H 2 And CO 2 。
Gong Weimin et al (Effects of Hydrogen on the Methane Coupling under Non-equilibrium Plasma [ J)].Plasma Science and Technology,2001,3(1):637-9./Study on the Methane Coupling under Pulse Corona Plasma by Using CO 2 as Oxidant[J].Plasma Science and Technology,2000,2(6):577-80./Study on the hydrogenation coupling of methane[J].Science China Chemistry,2001,44(2):191-5./Methane Coupling Using Hydrogen Plasma and Pt/γ—Al 2 O 3 Catalyst[J].Chin Chem Lett,2002,13(8):711-3./The simultaneous activation of methane and carbon dioxide to C2 hydrocarbons under pulse corona plasma over La 2 O 3 /γ-Al 2 O3 catalyst[J]Catalyst Today,2002,72 (3): 223-7.) methane corona discharge studies using needle plate reactors examined H 2 、CO 2 The effect of the addition of (c) on methane conversion and also the conversion of methane in the presence of corona discharge-catalyst synergy was studied in detail. Along with H 2 /CH 4 Increase of proportion, CH 4 Conversion, C 2 The yield is increased, C in the product 2 H 6 、C 2 H 4 Increased content of C 2 H 2 The content is reduced; and at H 2 Investigation of Ni/gamma-Al in the presence of 2 O 3 、Pt/γ-Al 2 O 3 Methane conversion in the system was found to be 6X 10 -5 wt％Pt/γ-Al 2 O 3 The better reaction results obtained in the catalyst are: methane conversion 33.3%, C 2 Hydrocarbon selectivity 67.5% (where C 2 H 4 59.32 percent of C 2 H 6 18.6% C 2 H 2 22.3%) C 4 Hydrocarbon selectivity was 2.3%. When CO is added 2 When in use, with CO 2 Increased content of C 2 Reduced hydrocarbon yield (C) 2 C in hydrocarbons 2 H 2 Reduced content of C 2 H 6 、C 2 H 4 An increase in content); and at CO 2 Investigation of gamma-Al in the presence of 2 O 3 、La 2 O 3/ γ-Al 2 O 3 、Pd/γ-Al 2 O 3 、Pd-La 2 O 3 /γ-Al 2 O 3 Methane conversion in Pd-La 2 O 3 /γ-Al 2 O 3 The better reaction result obtained in the catalyst is CH 4 Conversion 23.8%, CO 2 Conversion 22.0%, C 2 Yield 16.7% (C) 2 Selectivity of 70.4% where C 2 H 6 Accounting for 25.4 percent, C 2 H 4 65.4% C 2 H 2 0% CO yield 23.4%.
However, the direct conversion of methane to olefins by plasma is not reported in the prior art.
Disclosure of Invention
The invention aims to overcome the defect of low conversion efficiency of converting methane into olefin in the prior art.
In order to achieve the above object, a first aspect of the present invention provides a sliding arc plasma reactor comprising a first reactor inlet, a second reactor inlet, a tubular electrode sliding arc generator comprising a first gas nozzle, a second gas nozzle, a tubular electrode and a base, a lower reaction zone and a product outlet;
at least 2 tubular electrodes which are symmetrically distributed are arranged on the base of the tubular electrode sliding arc generator, so that a discharge area can be formed between the tubular electrodes; the base is provided with the first gas nozzle and the tubular electrode is provided with the second gas nozzle, so that reaction gas can enter the sliding arc plasma reactor from the first reactor inlet through the first gas nozzle and/or from the second reactor inlet through the second gas nozzle; and
The tubular electrodes are tubular structures with fully-closed cambered surfaces, and the tubular structures of every 2 tubular electrodes which are symmetrically distributed correspond to each other so as to be capable of generating discharge.
In a second aspect, the present invention provides a method for efficiently converting methane by plasma, the method being implemented in the sliding arc plasma reactor according to the first aspect, the method comprising:
under plasma discharge conditions, introducing a reaction gas containing methane into the sliding arc plasma reactor through the first reactor inlet and the first gas nozzle, so that the reaction gas sequentially passes through a discharge region formed by the tubular electrode and the lower reaction region to perform methane conversion reaction, and a product obtained after the reaction is led out of the sliding arc plasma reactor through the product outlet.
In a third aspect, the present invention provides a method for efficiently converting methane by plasma, the method being implemented in the sliding arc plasma reactor according to the first aspect, the method comprising:
under plasma discharge conditions, introducing a reaction gas containing methane into the sliding arc plasma reactor through the second reactor inlet and the second gas nozzle, so that the reaction gas sequentially passes through a discharge region formed by the tubular electrode and the lower reaction region to perform methane conversion reaction, and a product obtained after the reaction is led out of the sliding arc plasma reactor through the product outlet.
In a fourth aspect, the present invention provides a method for efficiently converting methane by plasma, the method being implemented in the sliding arc plasma reactor according to the first aspect, the method comprising:
under plasma discharge conditions, a reaction gas containing methane is introduced into the sliding arc plasma reactor through the first reactor inlet and the first gas nozzle, and the reaction gas is introduced into the sliding arc plasma reactor through the second reactor inlet and the second gas nozzle, so that the reaction gas sequentially passes through a discharge region formed by the tubular electrode and the lower reaction region to perform a methane conversion reaction, and a product obtained after the reaction is discharged from the sliding arc plasma reactor through the product outlet.
Compared with the prior art, the scheme provided by the invention has at least the following advantages:
(1) The sliding arc plasma reactor provided by the invention adopts the tubular electrode to form the discharge area, and the discharge area is discharged into the arc point on the curved surface, so that more arc channels are formed, and the reactant conversion capability is stronger;
(2) The gas inlet structure of the sliding arc plasma reactor provided by the invention can enable raw gas to more intensively pass through a discharge area formed by the tubular electrode, so that the gas flow passing through the discharge area is effectively increased, the conversion efficiency of reactants is improved, and the energy consumption is reduced;
(3) The sliding arc plasma reactor provided by the invention can realize the efficient generation of olefin through one-step conversion of methane under higher conversion efficiency of reactants, can maintain continuous and stable reaction, and has no CO compared with the traditional process for preparing olefin by methane 2 The production is safe and environment-friendly, and the explosion risk is avoided.
Additional features and advantages of the invention will be set forth in the detailed description which follows.
Drawings
Fig. 1 is a schematic structural view of a preferred embodiment of a sliding arc plasma reactor according to the present invention.
Description of the reference numerals
11. First reactor inlet 12 second reactor inlet
21. First gas nozzle 22 second gas nozzle
3. The lower reaction zone of the tubular electrode 4
5. Product outlet 6 base
7. Movable connecting mechanism
Detailed Description
The endpoints and any values of the ranges disclosed herein are not limited to the precise range or value, and are understood to encompass values approaching those ranges or values. For numerical ranges, one or more new numerical ranges may be found between the endpoints of each range, between the endpoint of each range and the individual point value, and between the individual point value, in combination with each other, and are to be considered as specifically disclosed herein.
As previously described, a first aspect of the present invention provides a sliding arc plasma reactor comprising a first reactor inlet, a second reactor inlet, a tubular electrode sliding arc generator comprising a first gas nozzle, a second gas nozzle, a tubular electrode and a base, a lower reaction zone and a product outlet;
at least 2 tubular electrodes which are symmetrically distributed are arranged on the base of the tubular electrode sliding arc generator, so that a discharge area can be formed between the tubular electrodes; the base is provided with the first gas nozzle and the tubular electrode is provided with the second gas nozzle, so that reaction gas can enter the sliding arc plasma reactor from the first reactor inlet through the first gas nozzle and/or from the second reactor inlet through the second gas nozzle; and
the tubular electrodes are tubular structures with fully-closed cambered surfaces, and the tubular structures of every 2 tubular electrodes which are symmetrically distributed correspond to each other so as to be capable of generating discharge.
In the invention, the arc point of the tubular electrode is on the curved surface, so that more discharge areas of the arc channel can be formed, and the reactant conversion capability is stronger.
Preferably, in the present invention, the symmetrical distribution is symmetrical distribution based on a central vertical axis of the base. The mounting position of the tubular electrode does not affect the discharge.
In the present invention, the shape and material of the base are not particularly limited, and may be circular or any other shape capable of achieving the aforementioned object of the present invention, and may be an insulating material or any other material capable of achieving the aforementioned object of the present invention.
Preferably, 2 tubular electrodes or 6 tubular electrodes are symmetrically distributed on the base of the tubular electrode sliding arc generator.
According to a preferred embodiment, 2 tubular electrodes are arranged symmetrically on the base of the tubular electrode sliding arc generator.
Preferably, the center of the base is provided with the first gas nozzle, and the second gas nozzle is arranged in the opposite direction of each 2 tubular electrodes in symmetrical positions, the first gas nozzle is communicated with the gas inlet pipeline of the first reactor inlet, and the second gas nozzle is communicated with the gas inlet pipeline of the second reactor inlet.
In the present invention, "each 2 of the tubular electrodes at symmetrical positions" means that the present invention does not limit the tubular electrodes at only 2 symmetrical positions, but the 2 tubular electrodes at symmetrical positions are specifically limited.
In the present invention, the arrangement of the second gas nozzles is not particularly limited, and a plurality of second gas nozzles may be arranged on the tubular electrode, and the heights of the second gas nozzles arranged in the opposite direction may be aligned with each other or may be staggered with each other.
Preferably, the material forming the first gas nozzle is at least one selected from a conductive material and an insulating material.
More preferably, the material forming the first gas nozzle is an insulating material.
According to a preferred embodiment, the material forming the first gas nozzle is an electrically conductive material, and the outlet position of the first gas nozzle does not overlap the tubular electrode in the vertical direction.
Preferably, the material forming the tubular electrode is a conductive material.
More preferably, the conductive material is at least one selected from 316L stainless steel, tungsten-cerium alloy, nichrome, cobalt-chromium-nickel alloy, cobalt-cadmium-nickel alloy, nickel-copper alloy, cobalt-copper-nickel alloy, cobalt-nickel alloy, and graphite. The material forming the tubular electrode can also be other high temperature resistant and arc corrosion resistant conductive materials.
Preferably, the tubular electrode is connected to the base by a movable connection mechanism, so that the tubular electrode can be freely adjusted in position in a lower region of the base.
In the present invention, the manner in which the movable connection mechanism is connected to the base is not particularly limited, and may be fixedly connected or movably connected. The freely adjustable position is an adjustment position in various directions, and is not limited to the position shown in the embodiment of fig. 1.
More preferably, the tubular electrode is connected to the base by a movable connection mechanism, so that the tubular electrode can be adjusted in position in the vertical direction and in the horizontal direction.
Preferably, the movable connection mechanism is vertically connected with the base.
In the invention, the movable connecting mechanism can be connected with the base in a non-vertical way.
Preferably, the tubular electrode is rotatably connected with the movable connecting mechanism, so that the tubular electrode can rotate freely to adjust the angle.
More preferably, the tubular electrode is rotatably connected with the movable connecting mechanism, so that the tubular electrode can rotate to adjust an included angle with the vertical direction.
Preferably, the included angle θ is 5 ° to 160 °, more preferably 10 ° to 90 °, still more preferably 30 ° to 60 °, within the extension line of the symmetry axis of each 2 of the tubular electrodes in the symmetrical position.
The sliding arc plasma reactor provided by the invention can enable the raw material gas to more intensively pass through the discharge area formed by the tubular electrode, thereby effectively increasing the gas flow passing through the discharge area and improving the conversion efficiency of reactants.
Preferably, the outer cylinder of the sliding arc plasma reactor is formed of at least one material selected from an insulating material, a conductive material, and a conductive material provided with an insulating lining.
More preferably, the outer cylinder of the sliding arc plasma reactor is formed of an insulating material or a conductive material provided with an insulating lining.
Further preferably, the insulating material is at least one selected from the group consisting of plain glass, quartz glass, and corundum.
In the invention, the material forming the outer cylinder can be conductive material on the premise of avoiding the contact between the tubular electrode and the outer cylinder of the sliding arc plasma reactor.
In the present invention, the shape of the outer tube of the sliding arc plasma reactor is not particularly limited, and the reactor may be provided with a closed space, and may be cylindrical, rectangular, or any other shape that can achieve the above-described object of the present invention.
Preferably, the material forming the lower reaction zone is a metallic material.
Preferably, the lower reaction zone is tapered. The inventors have found that this shape is more advantageous for the distribution of the reactant gases.
Preferably, the lower reaction zone is a reaction zone capable of being provided with a catalyst bed layer having a thickness such that the space velocity when passing the feed gas is 1000 to 10000h -1 Preferably 5000-8000h -1 。
The sliding arc plasma reactor provided by the invention can be filled with a catalyst capable of catalyzing the conversion of acetylene to olefin, and the catalyst is preferably filled in the lower reaction zone of the reactor. The loading volume and loading type of the catalyst are not particularly limited in the present invention, and may be any of various catalysts known in the art for catalyzing the conversion of acetylene to olefins, and the following description of the present invention exemplifies a specific catalyst and should not be construed as limiting the present invention.
In the present invention, it is particularly preferred that the catalyst comprises a Ti oxide-doped support and an active component supported on the support, wherein the active component contains a first active component selected from at least one of a group VIII non-noble metal and a group IB metal and a second active component selected from at least one of a group VIII noble metal, and the weight ratio of the first active component to the second active component is 0.1 to 200 in terms of metal element: 1.
The sliding arc plasma reactor provided by the invention can realize continuous and stable reaction under higher reactant conversion efficiency, and compared with the traditional methane-to-olefin process, the sliding arc plasma reactor has no CO 2 The production is safe and environment-friendly, and the explosion risk is avoided.
As previously mentioned, a second aspect of the present invention provides a method for efficiently converting methane by plasma, the method being carried out in a sliding arc plasma reactor as described in the first aspect, the method comprising:
under plasma discharge conditions, introducing a reaction gas containing methane into the sliding arc plasma reactor through the first reactor inlet and the first gas nozzle, so that the reaction gas sequentially passes through a discharge region formed by the tubular electrode and the lower reaction region to perform methane conversion reaction, and a product obtained after the reaction is led out of the sliding arc plasma reactor through the product outlet.
As previously mentioned, a third aspect of the present invention provides a method for efficiently converting methane by plasma, the method being implemented in a sliding arc plasma reactor as described in the first aspect, the method comprising:
under plasma discharge conditions, introducing a reaction gas containing methane into the sliding arc plasma reactor through the second reactor inlet and the second gas nozzle, so that the reaction gas sequentially passes through a discharge region formed by the tubular electrode and the lower reaction region to perform methane conversion reaction, and a product obtained after the reaction is led out of the sliding arc plasma reactor through the product outlet.
As previously mentioned, a fourth aspect of the present invention provides a method for efficiently converting methane by plasma, the method being carried out in a sliding arc plasma reactor as described in the first aspect, the method comprising:
under plasma discharge conditions, a reaction gas containing methane is introduced into the sliding arc plasma reactor through the first reactor inlet and the first gas nozzle, and the reaction gas is introduced into the sliding arc plasma reactor through the second reactor inlet and the second gas nozzle, so that the reaction gas sequentially passes through a discharge region formed by the tubular electrode and the lower reaction region to perform a methane conversion reaction, and a product obtained after the reaction is discharged from the sliding arc plasma reactor through the product outlet.
The sliding arc plasma reactor provided by the present invention is not particularly limited in terms of the reaction conditions involved in converting methane to olefins, and may be carried out under various conditions involved in the plasma methane conversion processes conventionally employed in the art, and the examples of the present invention are partially exemplified by the conditions for converting methane to olefins, and those skilled in the art should not be construed as limiting the present invention.
The concentration of methane in the reaction gas at the inlet of the sliding arc plasma reactor provided by the present invention is not particularly limited, and for example, the concentration of methane in the gas may be 0.01 to 100% by volume, and may be, for example, 5% by volume, 10% by volume, 15% by volume, 20% by volume, 25% by volume, 30% by volume, 35% by volume, 40% by volume, 45% by volume, 50% by volume, 55% by volume, 60% by volume, 65% by volume, 70% by volume, 75% by volume, 80% by volume, 85% by volume, 90% by volume, and 95% by volume.
In the invention, after the reaction gas passes through the discharge area formed by the tubular electrode, heat generated by discharge and reactants enter the lower reaction area, the heat can provide heat required by the catalyst bed layer in the lower reaction area, the catalyst bed layer is not required to be additionally heated, and the energy consumption can be reduced on the premise of not influencing the conversion efficiency.
The structure of a preferred embodiment of the sliding arc plasma reactor of the present invention, in particular, is provided below in conjunction with fig. 1:
the reactor comprises a first reactor inlet 11, a second reactor inlet 12, a tubular electrode sliding arc generator, a lower reaction zone 4 and a product outlet 5, wherein the tubular electrode sliding arc generator comprises a first gas nozzle 21, a second gas nozzle 22, a tubular electrode 3, a base 6 and a movable connecting mechanism 7;
Wherein, 2 tubular electrodes 3 which are symmetrically distributed are arranged on the base 6 of the tubular electrode sliding arc generator, so that a discharge area can be formed between the tubular electrodes 3; the center of the base 6 is provided with the first gas nozzle 21, and the second gas nozzle 22 is provided in the opposite direction of the tubular electrode 3, the first gas nozzle 21 communicates with the gas inlet pipe of the first reactor inlet 11, and the second gas nozzle 22 communicates with the gas inlet pipe of the second reactor inlet 12, so that the reaction gas can enter the sliding arc plasma reactor from the first reactor inlet 11 through the first gas nozzle 21 and/or from the second reactor inlet 12 through the second gas nozzle 22.
Preferably, the tubular electrode 3 is connected to the base 6 by a movable connection 7, so that the tubular electrode 3 can be adjusted in position in the vertical direction and in the horizontal direction.
Preferably, the movable connection mechanism 7 is vertically connected with the base 6.
Preferably, the tubular electrode 3 is rotatably connected with the movable connecting mechanism 7, so that the tubular electrode 3 can rotate to adjust an included angle with the vertical direction.
Another preferred embodiment for converting methane using the sliding arc plasma reactor of the present invention is provided below:
nitrogen is introduced into the sliding arc plasma reactor from the first reactor inlet and/or the second reactor inlet to purge air in the discharge region and to draw gas out of the product outlet. And then introducing reaction gas containing methane into the sliding arc plasma reactor from the first reactor inlet and/or the second reactor inlet, switching on a high-voltage power supply after the gas flow of the reaction gas is stable, and forming a plasma discharge field between the tubular electrodes by adjusting the voltage and the frequency. The reaction gas sequentially passes through a discharge area and a lower reaction area formed by the tubular electrodes to respectively carry out ionization and hydrogenation reactions, and a product obtained after the reaction is led out of the sliding arc plasma reactor through a product outlet.
The invention will be described in detail below by way of examples.
In the following examples, unless otherwise specified, all materials involved are commercially available.
In the examples below, methane conversion, ethylene selectivity, ethane selectivity, acetylene selectivity, C 3 The hydrocarbon selectivity and carbon deposition are respectively calculated according to the following formulas:
Methane conversion% = (amount of methane material before reaction-amount of methane material after reaction)/amount of methane material before reaction x 100%;
hydrocarbons (C) n H m ) Product selectivity = (post reaction C n H m The amount of substance) ×n/(the amount of methane substance before reaction-the amount of methane substance after reaction) ×100%, n=an integer of 2 to 5;
carbon deposition% = 1-hydrocarbons (C n H m ) Product selectivity, n=an integer from 2 to 5.
Preparation example 1
Dissolving palladium nitrate in deionized water to form a palladium nitrate solution (palladium content is 18 wt%), and dissolving copper nitrate in deionized water to form a copper nitrate solution (copper content is 30 wt%), wherein the mixing ratio of the palladium nitrate solution and the copper nitrate solution is that palladium loading amount accounts for 0.5 wt% of the catalyst mass, copper loading amount accounts for 1 wt% of the catalyst mass, and TiO is adopted 2 -Al 2 O 3 The carrier is prepared by mixing the two solutions by an excessive impregnation method, impregnating for 12 hours, drying for 4 hours at 80 ℃ by rotary evaporation, then placing the carrier into an oven at 120 ℃ for further drying for 8 hours, then placing the carrier into a muffle furnace for roasting for 5 hours at 450 ℃ to obtain a catalyst 1, wherein the chemical composition is as follows:
pd element content is 0.5 wt%, cu element content is 1 wt%, and the balance is TiO 2 -Al 2 O 3 The method comprises the steps of carrying out a first treatment on the surface of the The particle size of the active component was 5.4nm and the L acid/B acid 15.6.
Example 1
The sliding arc plasma reactor is adopted for methane conversion reaction, and the specific structure and the structural parameters of the reactor are as follows:
the reactor comprises a first reactor inlet, a second reactor inlet, a tubular electrode sliding arc generator, a lower reaction zone and a product outlet, wherein the tubular electrode sliding arc generator comprises a first gas nozzle, a second gas nozzle, a tubular electrode, a base and a movable connecting mechanism;
wherein, 2 tubular electrodes which are symmetrically distributed are arranged on the base of the tubular electrode sliding arc generator, so that a discharge area can be formed between the tubular electrodes; the center of the base is provided with the first gas nozzle, and the opposite direction of the tubular electrode is provided with the second gas nozzle, the first gas nozzle is communicated with the gas inlet pipeline of the first reactor inlet, and the second gas nozzle is communicated with the gas inlet pipeline of the second reactor inlet, so that reaction gas can enter the sliding arc plasma reactor from the first reactor inlet through the first gas nozzle and/or from the second reactor inlet through the second gas nozzle;
The tubular electrode is connected with the base through a movable connecting mechanism, so that the position of the tubular electrode can be adjusted along the vertical direction and the horizontal direction; the movable connecting mechanism is vertically connected with the base; the tubular electrode is rotatably connected with the movable connecting mechanism, so that the tubular electrode can rotate to adjust an included angle with the vertical direction;
the second gas nozzles are arranged in a staggered manner in the opposite direction of the tubular electrode;
the material forming the tubular electrode is cobalt-cadmium-nickel alloy;
the included angle theta in the extension lines of the symmetrical axes of the 2 tubular electrodes at the symmetrical positions is 50 degrees;
the outer cylinder of the sliding arc plasma reactor is made of quartz glass;
the thickness of the catalyst bed layer is such that the space velocity of the feed gas passing through the catalyst bed layer is 2000h -1 ；
The sliding arc plasma reactor in this example has a volume of 3L.
The operating conditions of the sliding arc plasma reactor in this example are as follows:
the discharge power is adjusted to 280W, the voltage is 2.5kV, the discharge frequency is 24.0kHz, the air inflow is 2.6L/min of methane, and the hydrogen gas is 2.0L/min; the height of the catalyst bed layer filled in the lower reaction zone of the reactor is 15mm, and the dosage of the catalyst is 60g; the catalyst is the catalyst 1 prepared in the preparation example 1;
Introducing nitrogen into the reactor through an inlet of the reactor for 30min, wherein the air inflow rate is 4L/min, replacing oxygen in the reactor, then introducing mixed gas (the air inflow rate is 2.5L/min for nitrogen and 2.5L/min for hydrogen), starting a power supply, adjusting the voltage and the frequency, adjusting the voltage to 3.5kV, adjusting the frequency to 22.5kHz, starting discharging, reducing the catalyst in the lower reaction zone for about 3.0h, basically blackening the catalyst color, and ending the reduction; turning off a power supply, then introducing mixed gas (the air inflow rate is 2.6L/min for methane and 2.0L/min for hydrogen), turning on the power supply, adjusting the voltage and the frequency, adjusting the voltage to 2.0kV, adjusting the frequency to 24.0kHz, starting discharging, adjusting the voltage to the appointed 2.5kV, and reacting for 8 hours at the moment that the power is 280W;
the tail gas was analyzed and the results were: methane conversion was 51.3%, ethylene selectivity was 90.2%, ethane selectivity was 5.2%, C 3 The selectivity of the hydrocarbon is 4.6 percent, and no obvious carbon deposit exists.
Example 2
This example uses a sliding arc plasma reactor similar to example 1 for the methane conversion reaction, except that in this example:
arranging the second gas nozzles in mutual alignment in opposite directions of the tubular electrodes;
The material forming the tubular electrode is 316L stainless steel;
the included angle theta in the extension lines of the symmetrical axes of the 2 tubular electrodes at the symmetrical positions is 38 degrees;
the outer cylinder of the sliding arc plasma reactor is made of 304 stainless steel with a quartz lining;
the thickness of the catalyst bed layer is such that the space velocity of the raw material gas passing through the catalyst bed layer is 6000h -1 ；
The sliding arc plasma reactor in this example had a volume of 4L.
In the embodiment, the discharge power is adjusted to 150W, the voltage is 1.8kV, the discharge frequency is 13.5kHz, the air inflow is 0.8L/min of methane, and the air inflow is 1.5L/min of hydrogen;
introducing nitrogen into the reactor through an inlet of the reactor for 30min, wherein the air inflow rate is 1.5L/min, replacing oxygen in the reactor, then introducing mixed gas (the air inflow rate is 2.5L/min for nitrogen and 2.5L/min for hydrogen), starting a power supply, adjusting the voltage and the frequency, adjusting the voltage to 2.7kV, adjusting the frequency to 13.5kHz, starting discharging, reducing the catalyst in the lower reaction zone for about 4.0h, and ending the reduction, wherein the color of the catalyst is basically blackened; and (3) turning off the power supply, then introducing mixed gas (the air inflow rate is 0.8L/min for methane and 1.5L/min for hydrogen), turning on the power supply, adjusting the voltage and the frequency, adjusting the voltage to 1.5kV, adjusting the frequency to 13.5kHz, starting discharging, adjusting the voltage to the designated 1.8kV, and reacting for 8 hours at the moment that the power is 150W.
The remainder was the same as in example 1.
The tail gas was analyzed and the results were: methane conversion was 52.7%, ethylene selectivity was 88.1%, ethane selectivity was 6.2%, C 3 The selectivity of the hydrocarbon is 5.8%, and no obvious carbon deposit exists.
Example 3
This example uses a sliding arc plasma reactor similar to example 1 for the methane conversion reaction, except that in this example:
arranging the second gas nozzles in mutual alignment in opposite directions of the tubular electrodes;
the material forming the tubular electrode is nickel-copper alloy;
the included angle theta in the extension lines of the symmetry axes of the 2 tubular electrodes at the symmetrical positions is 125 degrees;
the outer cylinder of the sliding arc plasma reactor is made of toughened glass;
the thickness of the catalyst bed layer is such that the space velocity when passing through the feed gas is 8000h -1 ；
The sliding arc plasma reactor in this example had a volume of 3.3L.
In the embodiment, the discharge power is adjusted to 210W, the voltage is 4.5kV, the discharge frequency is 20.4kHz, the air inlet flow is 1.6L/min of methane and 1.9L/min of hydrogen;
introducing nitrogen into the reactor through an inlet of the reactor for 30min, wherein the air inflow rate is 2L/min, replacing oxygen in the reactor, then introducing mixed gas (the air inflow rate is 1.5L/min for nitrogen and 1.5L/min for hydrogen), starting a power supply, adjusting the voltage and the frequency, adjusting the voltage to 3.5kV, adjusting the frequency to 20.4kHz, starting discharging, reducing the catalyst in the lower reaction zone for about 3.2h, basically blackening the catalyst color, and ending the reduction; and (3) turning off the power supply, then introducing mixed gas (the air inflow rate is 1.6L/min for methane and 1.9L/min for hydrogen), turning on the power supply, adjusting the voltage and the frequency, adjusting the voltage to 4.0kV, adjusting the frequency to 20.4kHz, starting discharging, adjusting the voltage to the designated 4.5kV, and reacting for 8 hours at the moment that the power is 210W.
The remainder was the same as in example 1.
The tail gas was analyzed and the results were: methane conversion was 53.4%, ethylene selectivity was 91.3%, ethane selectivity was 4.1%, C 3 The selectivity of the hydrocarbon is 4.6 percent, and no obvious carbon deposit exists.
Example 4
This example uses a sliding arc plasma reactor similar to example 1 for the methane conversion reaction, except that in this example:
the material for forming the tubular electrode is cobalt-copper-nickel alloy;
the included angle theta in the extension lines of the symmetrical axes of the 2 tubular electrodes at the symmetrical positions is 75 degrees;
the outer cylinder of the sliding arc plasma reactor is made of ceramic;
the thickness of the catalyst bed layer is such that the space velocity when passing through the raw material gas is 3500h -1 ；
The sliding arc plasma reactor in this example had a volume of 5L.
In the embodiment, the discharge power is adjusted to 127W, the voltage is 5.1kV, the discharge frequency is 16.8kHz, and the air inflow is 1.0L/min of methane and 2.0L/min of hydrogen;
introducing nitrogen into the reactor through an inlet of the reactor for 30min, wherein the air inflow rate is 2.5L/min, replacing oxygen in the reactor, then introducing mixed gas (the air inflow rate is 3.0L/min for nitrogen and 1.5L/min for hydrogen), starting a power supply, adjusting the voltage and the frequency, adjusting the voltage to 4.0kV, adjusting the frequency to 16.8kHz, starting discharging, reducing the catalyst in the lower reaction zone for about 4.5h, and ending the reduction, wherein the color of the catalyst is basically blackened; and (3) turning off the power supply, then introducing mixed gas (the air inflow rate is 1.0L/min for methane and 2.0L/min for hydrogen), turning on the power supply, adjusting the voltage and the frequency, adjusting the voltage to 4.0kV, adjusting the frequency to 16.8kHz, starting discharging, adjusting the voltage to 5.1kV, and reacting for 8 hours at the moment that the power is 127W.
The remainder was the same as in example 1.
The tail gas was analyzed and the results were: methane conversion was 52.8%, ethylene selectivity was 91.2%, ethane selectivity was 5.3%, C 3 The selectivity of the hydrocarbon is 3.5 percent, and no obvious carbon deposit exists.
Example 5
This example uses a sliding arc plasma reactor similar to example 1 for the methane conversion reaction, except that in this example:
the material for forming the tubular electrode is cobalt-copper-nickel alloy;
the included angle theta in the extension lines of the symmetrical axes of the 2 tubular electrodes at the symmetrical positions is 39 degrees;
the outer cylinder of the sliding arc plasma reactor is made of 316L stainless steel with a quartz lining;
the thickness of the catalyst bed layer is such that the space velocity when passing through the feed gas is 9000h -1 ；
The sliding arc plasma reactor in this example had a volume of 6.2L.
In the embodiment, the discharge power is adjusted to 185W, the voltage is 2.3kV, the discharge frequency is 24.8kHz, and the air inflow is 1.2L/min of methane and 2.0L/min of hydrogen;
introducing nitrogen into the reactor through an inlet of the reactor for 30min, wherein the air inflow rate is 2.5L/min, replacing oxygen in the reactor, then introducing mixed gas (the air inflow rate is 2.0L/min for nitrogen and 2.0L/min for hydrogen), starting a power supply, adjusting the voltage and the frequency, adjusting the voltage to 2.0kV, adjusting the frequency to 24.8kHz, starting discharging, reducing the catalyst in the lower reaction zone for about 4.0h, and ending the reduction, wherein the color of the catalyst is basically blackened; and (3) turning off the power supply, then introducing mixed gas (the air inflow rate is 1.2L/min for methane and 2.0L/min for hydrogen), turning on the power supply, adjusting the voltage and the frequency, adjusting the voltage to 2.0kV, adjusting the frequency to 24.8kHz, starting discharging, adjusting the voltage to the designated 2.3kV, and reacting for 8 hours at the moment that the power is 185W.
The remainder was the same as in example 1.
The tail gas was analyzed and the results were: methane conversion was 50.4%, ethylene selectivity was 89.4%, ethane selectivity was 6.9%, C 3 The selectivity of the hydrocarbon is 3.7 percent, and no obvious carbon deposit exists.
Example 6
This example uses a sliding arc plasma reactor similar to example 1 for the methane conversion reaction, except that in this example:
the material forming the tubular electrode is cobalt-nickel alloy;
the included angle theta in the extension lines of the symmetry axes of the 2 tubular electrodes at the symmetrical positions is 67 degrees;
the outer cylinder of the sliding arc plasma reactor is made of copper with a glass lining;
the thickness of the catalyst bed layer is such that when passing through the feed gasIs 7000h -1 ；
The sliding arc plasma reactor in this example had a volume of 5L.
In the embodiment, the discharge power is adjusted to 251W, the voltage is 3.8kV, the discharge frequency is 28.4kHz, the air inlet flow is 2.7L/min of methane and 3.0L/min of hydrogen;
introducing nitrogen into the reactor through an inlet of the reactor for 30min, wherein the air inflow rate is 3.0L/min, replacing oxygen in the reactor, then introducing mixed gas (the air inflow rate is 2.5L/min for nitrogen and 3.0L/min for hydrogen), starting a power supply, adjusting the voltage and the frequency, adjusting the voltage to 3.0kV, adjusting the frequency to 28.4kHz, starting discharging, reducing the catalyst in the lower reaction zone for about 5.0h, and ending the reduction, wherein the color of the catalyst is basically blackened; and (3) turning off the power supply, then introducing mixed gas (the air inflow rate is 2.7L/min for methane and 3.0L/min for hydrogen), turning on the power supply, adjusting the voltage and the frequency, adjusting the voltage to 3.0kV, adjusting the frequency to 28.4kHz, starting discharging, adjusting the voltage to the designated 3.8kV, and reacting for 8 hours at the moment that the power is 251W.
The remainder was the same as in example 1.
The tail gas was analyzed and the results were: methane conversion was 53.9%, ethylene selectivity was 90.2%, ethane selectivity was 6.2%, C 3 The selectivity of the hydrocarbon is 3.6 percent, and no obvious carbon deposit exists.
Comparative example 1
This comparative example uses a sliding arc plasma reactor similar to example 1 for the methane conversion reaction, except that in this comparative example:
the adopted electrode is a blade electrode, the material forming the blade electrode is 316L stainless steel, and specific references of the properties and parameters of the adopted blade electrode are as follows: zhong Li, et al, university of Zhejiang, journal of sliding arc discharge plasma methane reforming to make syngas: an ergonomic plate (2010);
the sliding arc plasma reactor in this comparative example had a volume of 2L.
In the comparative example, the discharge power is adjusted to 300W, the voltage is 3.0kV, the discharge frequency is 22.3kHz, and the air inflow is methane 1L/min and hydrogen 3L/min; the lower reaction zone of the reactor is not filled with a catalyst bed layer;
introducing nitrogen into the reactor through the inlet of the reactor for 30min, replacing oxygen in the reactor with air inflow of 3L/min, introducing mixed gas (air inflow of 1L/min for methane and 3L/min for hydrogen), starting a power supply, adjusting voltage and frequency, adjusting the voltage to 2.0kV, adjusting the frequency to 22.3kHz, starting discharging, adjusting the voltage to 3.0kV, and reacting for 8h with the power of 300W.
The remainder was the same as in example 1.
The tail gas was analyzed and the results were: methane conversion 23.7%, acetylene selectivity 56.2%, ethylene selectivity 2.3%, ethane selectivity 1.6%, C 3 The selectivity of the hydrocarbon is 0.5 percent and the carbon deposit is 39.4 percent.
Comparative example 2
This comparative example uses a sliding arc plasma reactor similar to example 1 for the methane conversion reaction, except that in this comparative example:
the adopted electrode is a blade electrode, the material forming the blade electrode is 316L stainless steel, and specific references of the properties and parameters of the adopted blade electrode are as follows: zhong Li, et al, university of Zhejiang, journal of sliding arc discharge plasma methane reforming to make syngas: an ergonomic plate (2010);
the thickness of the catalyst bed layer is such that the space velocity of the feed gas passing through the catalyst bed layer is 7000h -1 ；
The sliding arc plasma reactor in this comparative example had a volume of 2L.
In the comparative example, the discharge power is adjusted to 320W, the voltage is 5.0kV, the discharge frequency is 15.7kHz, and the air inflow is methane 1.5L/min and hydrogen 2L/min;
introducing nitrogen into the reactor through the inlet of the reactor for 30min, replacing oxygen in the reactor with an air inlet flow of 2L/min, introducing mixed gas (the air inlet flow is methane of 1.5L/min and hydrogen of 2L/min), starting a power supply, adjusting the voltage and the frequency, adjusting the voltage to 4.0kV, adjusting the frequency to 15.7kHz, starting discharging, adjusting the voltage to 5.0kV, and reacting for 8h with the power of 320W.
The remainder was the same as in example 1.
The tail gas was analyzed and the results were: methane conversion 26.5%, ethylene selectivity 55.4%, ethane selectivity 2.1%, acetylene selectivity 1.8%, C 3 The selectivity of the hydrocarbon is 0.6 percent and the carbon deposit is 40.1 percent.
The results show that the sliding arc plasma reactor provided by the invention can obviously improve the conversion rate of methane, reduce energy consumption, improve the selectivity of ethylene in the product and obviously reduce carbon deposition compared with the prior art when being used for methane conversion reaction. The reactor provided by the invention can realize continuous and stable reaction under higher reactant conversion efficiency, and compared with the traditional process for preparing olefin by methane, the reactor has no CO 2 The production is safe and environment-friendly, and the explosion risk is avoided.
The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, a number of simple variants of the technical solution of the invention are possible, including combinations of the individual technical features in any other suitable way, which simple variants and combinations should likewise be regarded as being disclosed by the invention, all falling within the scope of protection of the invention.
Claims (16)
1. A sliding arc plasma reactor, characterized in that the reactor comprises a first reactor inlet (11), a second reactor inlet (12), a tubular electrode sliding arc generator comprising a first gas nozzle (21), a second gas nozzle (22), a tubular electrode (3) and a base (6), a lower reaction zone (4) and a product outlet (5);
wherein, at least 2 tubular electrodes (3) which are symmetrically distributed are arranged on the base (6) of the tubular electrode sliding arc generator, so that a discharge area can be formed between the tubular electrodes (3); -said first gas nozzle (21) is provided on said base (6) and said second gas nozzle (22) is provided on said tubular electrode (3) such that reaction gas can enter said sliding arc plasma reactor from said first reactor inlet (11) through said first gas nozzle (21) and/or from said second reactor inlet (12) through said second gas nozzle (22); and
the tubular electrodes (3) are tubular structures with fully-closed cambered surfaces, and the tubular structures of every 2 tubular electrodes (3) which are symmetrically distributed correspond to each other so as to be capable of generating discharge.
2. A sliding arc plasma reactor according to claim 1, wherein 2 of the tubular electrodes (3) or 6 of the tubular electrodes (3) are arranged symmetrically on the base (6) of the tubular electrode sliding arc generator.
3. A sliding arc plasma reactor according to claim 1 or 2, wherein the base (6) is centrally provided with the first gas nozzle (21) and symmetrically positioned with the second gas nozzle (22) in opposite direction of each of the 2 tubular electrodes (3), the first gas nozzle (21) being in communication with the gas inlet duct of the first reactor inlet (11), the second gas nozzle (22) being in communication with the gas inlet duct of the second reactor inlet (12).
4. A sliding arc plasma reactor according to any one of claims 1-3, wherein the material forming the first gas nozzle (21) is selected from at least one of a conductive material, an insulating material, preferably an insulating material.
5. The sliding arc plasma reactor of any of claims 1-4 wherein the material forming the first gas nozzle (21) is an electrically conductive material and the exit position of the first gas nozzle (21) is non-overlapping in the vertical direction with the tubular electrode (3).
6. A sliding arc plasma reactor according to any one of claims 1-5, wherein the material forming the tubular electrode (3) is an electrically conductive material;
Preferably, the conductive material is at least one selected from 316L stainless steel, tungsten-cerium alloy, nickel-chromium alloy, cobalt-chromium-nickel alloy, cobalt-cadmium-nickel alloy, nickel-copper alloy, cobalt-copper-nickel alloy, cobalt-nickel alloy and graphite.
7. The sliding arc plasma reactor of any one of claims 1-6 wherein the tubular electrode (3) is connected to the base (6) by a movable connection mechanism (7) such that the tubular electrode (3) can be freely adjusted in position in the area below the base (6);
preferably, the tubular electrode (3) is connected with the base (6) through a movable connecting mechanism (7), so that the position of the tubular electrode (3) can be adjusted along the vertical direction and the horizontal direction.
8. A sliding arc plasma reactor according to claim 7 wherein the articulating mechanism (7) is connected perpendicularly to the base (6).
9. The sliding arc plasma reactor of claim 7 or 8 wherein the tubular electrode (3) is rotatably connected to the articulating mechanism (7) such that the tubular electrode (3) can be freely rotated to adjust the angle;
preferably, the tubular electrode (3) is rotatably connected with the movable connecting mechanism (7), so that the tubular electrode (3) can rotate to adjust an included angle with the vertical direction.
10. A sliding arc plasma reactor according to any one of claims 1-9, wherein the included angle θ in extension of the symmetry axis of each 2 of the tubular electrodes (3) in symmetrical positions is 5 ° -160 °, preferably 10 ° -90 °, more preferably 30 ° -60 °.
11. The sliding arc plasma reactor according to any one of claims 1 to 10, wherein the outer barrel of the sliding arc plasma reactor is formed of at least one material selected from an insulating material, a conductive material provided with an insulating lining;
preferably, the outer cylinder of the sliding arc plasma reactor is formed of an insulating material or of a conductive material provided with an insulating lining.
12. A sliding arc plasma reactor according to any one of claims 1-11, wherein the material forming the lower reaction zone (4) is a metallic material;
preferably, the lower reaction zone (4) is tapered.
13. The sliding arc plasma reactor according to any one of claims 1-12, wherein the lower reaction zone (4) is a reaction zone capable of being provided with a catalyst bed having a thickness such that the space velocity through the feed gas is between 1000 and 10000h -1 Preferably 5000-8000h -1 。
14. A method for efficiently converting methane by plasma, characterized in that the method is carried out in a sliding arc plasma reactor according to any one of claims 1-13, the method comprising:
under plasma discharge conditions, a reaction gas containing methane is introduced into the sliding arc plasma reactor through the first reactor inlet (11) and the first gas nozzle (21) so that the reaction gas sequentially passes through a discharge region formed by the tubular electrode (3) and the lower reaction region (4) to perform a methane conversion reaction, and a product obtained after the reaction is led out of the sliding arc plasma reactor through the product outlet (5).
15. A method for efficiently converting methane by plasma, characterized in that the method is carried out in a sliding arc plasma reactor according to any one of claims 1-13, the method comprising:
under plasma discharge conditions, a reaction gas containing methane is introduced into the sliding arc plasma reactor through the second reactor inlet (12) and the second gas nozzle (22) so that the reaction gas sequentially passes through a discharge region formed by the tubular electrode (3) and the lower reaction region (4) to perform a methane conversion reaction, and a product obtained after the reaction is led out of the sliding arc plasma reactor through the product outlet (5).
16. A method for efficiently converting methane by plasma, characterized in that the method is carried out in a sliding arc plasma reactor according to any one of claims 1-13, the method comprising:
under plasma discharge conditions, a reaction gas containing methane is introduced into the sliding arc plasma reactor through the first reactor inlet (11) and the first gas nozzle (21), and the reaction gas is introduced into the sliding arc plasma reactor through the second reactor inlet (12) and the second gas nozzle (22), so that the reaction gas sequentially passes through a discharge region formed by the tubular electrode (3) and the lower reaction zone (4) to perform a methane conversion reaction, and a product obtained after the reaction is discharged from the sliding arc plasma reactor through the product outlet (5).
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111567218.1A CN116272758A (en) | 2021-12-20 | 2021-12-20 | Sliding arc plasma reactor and method for efficiently converting methane by plasma |
| PCT/CN2022/140057 WO2023116630A1 (en) | 2021-12-20 | 2022-12-19 | Gliding arc plasma reactor, and method for converting methane by means of plasma |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111567218.1A CN116272758A (en) | 2021-12-20 | 2021-12-20 | Sliding arc plasma reactor and method for efficiently converting methane by plasma |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116272758A true CN116272758A (en) | 2023-06-23 |
Family
ID=86794721
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111567218.1A Pending CN116272758A (en) | 2021-12-20 | 2021-12-20 | Sliding arc plasma reactor and method for efficiently converting methane by plasma |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116272758A (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090056222A1 (en) * | 2003-06-20 | 2009-03-05 | Gutsol Alexander F | Cyclonic reactor with non-equilibrium gliding discharge and plasma process for reforming of solid hydrocarbons |
| CN111947151A (en) * | 2020-08-07 | 2020-11-17 | 合肥中科远望环保科技有限公司 | Gas composite plasma torch |
| CN112020198A (en) * | 2020-08-07 | 2020-12-01 | 合肥中科远望环保科技有限公司 | Sliding arc plasma torch |
-
2021
- 2021-12-20 CN CN202111567218.1A patent/CN116272758A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090056222A1 (en) * | 2003-06-20 | 2009-03-05 | Gutsol Alexander F | Cyclonic reactor with non-equilibrium gliding discharge and plasma process for reforming of solid hydrocarbons |
| CN111947151A (en) * | 2020-08-07 | 2020-11-17 | 合肥中科远望环保科技有限公司 | Gas composite plasma torch |
| CN112020198A (en) * | 2020-08-07 | 2020-12-01 | 合肥中科远望环保科技有限公司 | Sliding arc plasma torch |
Non-Patent Citations (1)
| Title |
|---|
| ZAENAB ABD ALLAH 等: "plasma-catalytic dry reforming of methane in an atmospheric pressure AC gliding arc discharge", CATALYSIS TODAY, 8 May 2015 (2015-05-08), pages 76 - 78 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Goujard et al. | Use of a non-thermal plasma for the production of synthesis gas from biogas | |
| CN104071747B (en) | A kind of method that synthesis gas is prepared in plasma methane reformation | |
| Ni et al. | Reforming of methane and carbon dioxide by DC water plasma at atmospheric pressure | |
| WO2019154244A1 (en) | Plasma reaction device and method for decomposing hydrogen sulfide | |
| CN112624893A (en) | Catalytic coupling method of light alkane | |
| KR100561166B1 (en) | The apparatus and method for preparing synthesis gas by using barrier discharge reaction | |
| CN116272758A (en) | Sliding arc plasma reactor and method for efficiently converting methane by plasma | |
| RU2414418C2 (en) | Method of producing hydrogen and carbon nanofibres from hydrocarbon gas | |
| Wang et al. | A green process for high-concentration ethylene and hydrogen production from methane in a plasma-followed-by-catalyst reactor | |
| CN116272755A (en) | Sliding arc plasma reactor and method for generating olefin by directional conversion of methane by plasma | |
| CN116272754A (en) | Sliding arc plasma reactor and method for converting methane into olefin by plasma | |
| CN104725271B (en) | One methane and ammonia plasmas synthesizing amino acetonitrile and the method for N, N-Cyanamide, dimethyl- | |
| Lin et al. | Reforming of CH 4 and CO 2 by combination of alternating current-driven nonthermal arc plasma and catalyst | |
| KR20210148275A (en) | Apparatus and method for producing hydrogen and solid carbon from C1- to C4-alkane-containing gases | |
| CN116272759A (en) | Method for converting methane by using plasma | |
| Baowei et al. | Steam reforming of dimethyl ether by gliding arc gas discharge plasma for hydrogen production | |
| CN116272757A (en) | Method for preparing acetylene by converting methane through plasma | |
| WO2023116630A1 (en) | Gliding arc plasma reactor, and method for converting methane by means of plasma | |
| CN116283470A (en) | Method for generating acetylene by converting methane through plasma | |
| CN113072426B (en) | Method and device for synthesizing methanol by using carbon dioxide and methane | |
| US20230234018A1 (en) | Co2 methanation using plasma catalysis | |
| Qin et al. | Ni/MgO catalyst prepared using atmospheric high-frequency discharge plasma for CO2 reforming of methane | |
| KR100589202B1 (en) | The synthesis gas preparing apparatus and method for controlling the composition of synthesis gas | |
| CN114852996A (en) | System and method for preparing single-walled carbon nanotube by electric explosion method | |
| Ulejczyk et al. | Steam reforming of ethanol in spark discharge generated between electrodes made from a Ni 3 Al alloy |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |