WO2024082393A1 - 一种烃类原料高效转化的方法及其装置 - Google Patents

一种烃类原料高效转化的方法及其装置 Download PDF

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WO2024082393A1
WO2024082393A1 PCT/CN2022/137171 CN2022137171W WO2024082393A1 WO 2024082393 A1 WO2024082393 A1 WO 2024082393A1 CN 2022137171 W CN2022137171 W CN 2022137171W WO 2024082393 A1 WO2024082393 A1 WO 2024082393A1
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metal
halide
hydrogen
gas
halogen
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French (fr)
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管晓飞
张旭
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上海科技大学
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    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B1/00—Electrolytic production of inorganic compounds or non-metals
    • C25B1/01—Products
    • C25B1/24—Halogens or compounds thereof
    • C25B1/26—Chlorine; Compounds thereof
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B3/00—Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
    • C01B3/02—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen
    • C01B3/06—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of inorganic compounds containing electro-positively bound hydrogen, e.g. water, acids, bases, ammonia, with inorganic reducing agents
    • C01B3/08—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of inorganic compounds containing electro-positively bound hydrogen, e.g. water, acids, bases, ammonia, with inorganic reducing agents with metals
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B7/00—Halogens; Halogen acids
    • C01B7/01—Chlorine; Hydrogen chloride
    • C01B7/03—Preparation from chlorides
    • C01B7/035—Preparation of hydrogen chloride from chlorides
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B3/00—Electrolytic production of organic compounds
    • C25B3/01—Products
    • C25B3/03—Acyclic or carbocyclic hydrocarbons
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
    • C25C1/00—Electrolytic production, recovery or refining of metals by electrolysis of solutions

Definitions

  • the present application relates to the field of hydrocarbon feedstock conversion, and in particular, to a method and device for efficiently converting hydrocarbon feedstock.
  • Natural gas is abundant on earth and plays an important role in the global energy landscape.
  • the main components of natural gas are methane, followed by ethane and propane.
  • the main use of natural gas is as a fuel for heating.
  • less than 10% of natural gas is used as a chemical raw material. Due to the huge reserves of natural gas in shale gas, coalbed methane, and deep-sea combustible ice, the technology of using natural gas as a chemical raw material to produce high-value products has important environmental and economic significance.
  • a patent has disclosed a method for converting hydrocarbon feedstocks (including methane) into relatively unsaturated hydrocarbons, which specifically includes the following independent steps: (1) halogenating the hydrocarbon feedstock to form halogenated hydrocarbons, (2) converting the halogenated hydrocarbons into unsaturated hydrocarbons and hydrogen halides, (3) separating the unsaturated hydrocarbons from the halogenated hydrocarbons, and (4) electrolyzing the hydrogen halides in an aqueous medium or gas phase to hydrogen and molecular halogens.
  • the process can be achieved by repeating the above steps to achieve continuous production, it is complex, involves multiple independent steps and reaction chambers, is costly, and is therefore difficult to achieve large-scale operation.
  • the industrial steam pyrolysis method for preparing unsaturated hydrocarbons such as ethylene, propylene and butadiene from hydrocarbon feedstocks usually operates at temperatures exceeding 850°C and ultra-high pressures, which consumes a lot of energy. Globally, the steam pyrolysis process emits more than 300 million tons of carbon dioxide greenhouse gas each year. In summary, it is very important to find efficient, simple, low-cost, low-energy, low-emission and easy-to-scale hydrocarbon feedstock conversion processes.
  • the purpose of the present application is to provide a method and apparatus for converting hydrocarbon feedstocks to solve the problems of the prior art.
  • the present application provides a method for converting a hydrocarbon feedstock in a first aspect, comprising the following steps:
  • step 2) reacting the alkyl halide provided in step 1) with an active metal to generate a first unsaturated hydrocarbon and a first metal halide;
  • step 3 reacting the hydrogen halide provided in step 1) with an active metal to generate a second metal halide and hydrogen.
  • step 1) is carried out under a combination of one or more of an electrolysis system, light, and heating conditions.
  • the hydrocarbon raw material gas is selected from a combination of one or more of methane, ethane, propane, and natural gas.
  • the hydrocarbon raw material gas is selected from methane and/or ethane. More preferably, the hydrocarbon raw material gas is selected from ethane.
  • the halogen substance in step 1), includes a combination of one or more of halogen ions, halogen atoms, and halogen molecules.
  • the halogen atoms are selected from a combination of one or more of Cl, Br, and I.
  • the halogen ions include first halogen ions.
  • the halogen molecules include first halogen molecules and/or second halogen molecules. More preferably, the halogen ions are selected from a combination of one or more of Cl - , Br - , and I - .
  • the halogen molecules are selected from a combination of one or more of Cl 2 , Br 2 , and I 2 .
  • the alkyl halide includes a first alkyl halide and/or a second alkyl halide;
  • the hydrogen halide includes a first hydrogen halide and/or a third hydrogen halide.
  • the active metal in step 2) or step 3), includes a metal element and/or a liquid alloy.
  • Liquid alloy refers to a metal element dissolved in another metal with a low melting point.
  • the metal with a low melting point is selected from a combination of one or more of Ga, In, Sn, Pb, Zn, Bi, and Sb.
  • the metal element includes a first metal element.
  • the first metal element is selected from an alkali metal and/or an alkaline earth metal. More preferably, the first metal element is selected from a combination of one or more of Li, Na, K, Rb, Cs, Mg, Ca, Sr, and Ba.
  • the hydrogen includes the first hydrogen and/or the third hydrogen.
  • the electrolysis system when step 1) is performed in an electrolysis system, the electrolysis system comprises an anode, a cathode and a metal halide molten salt.
  • the metal halide molten salt provides a third metal halide in a molten state, the third metal halide is used to provide a first metal ion and a first halogen ion, and the first metal ion undergoes a reduction reaction at the cathode to provide a first metal element.
  • step 1) when step 1) is performed in an electrolysis system, the first halogen ion undergoes an oxidation reaction at the anode to provide a first halogen molecule, and the hydrocarbon feed gas undergoes an oxidation reaction with the first halogen molecule at the anode to provide a first alkyl halide and a first hydrogen halide.
  • the first halogen ions react with the hydrocarbon raw material gas through an oxidation reaction at the anode to provide a first alkyl halide and a first hydrogen halide.
  • At least a portion of the first alkyl halide and at least a portion of the first hydrogen halide diffuse to the cathode to undergo a reduction reaction to generate a combination of one or more of the first hydrogen gas, the second halogen ion, the first unsaturated hydrocarbon and the second metal halide.
  • the metal halide molten salt is selected from a melt of a third metal halide.
  • the third metal halide is selected from a combination of one or more of metal chlorides, metal bromides, and metal iodides. More preferably, the metal chloride is selected from a combination of one or more of LiCl, NaCl, KCl, RbCl, CsCl, MgCl 2 , CaCl 2 , SrCl 2 , BaCl 2 , and ZnCl 2.
  • the metal bromide is selected from a combination of one or more of LiBr, NaBr, KBr, RbBr, CsBr, MgBr 2 , CaBr 2 , SrBr 2 , BaBr 2 , and ZnBr 2.
  • the metal iodide is selected from a combination of one or more of LiI, NaI, KI, RbI, CsI, MgI 2 , CaI 2 , SrI 2 , BaI 2 , and ZnI 2 .
  • step 1) when step 1) is performed in an electrolysis system, the flow rate of the hydrocarbon raw material gas is 0.02-0.8 cm 3 /min for a unit volume of 1 cm 3 of the metal halide molten salt.
  • step 1) when step 1) is performed in an electrolytic system, the reaction temperature of the electrolyte system is 200-600° C.
  • the reaction voltage of the electrolyte system is 3-10V.
  • the reduction reaction when step 1) is performed in an electrolytic system, the reduction reaction includes: the third metal halide obtains electrons to provide a first metal element and a second halogen ion; the first metal element reacts with the first alkyl halide to generate a first unsaturated hydrocarbon and a first metal halide.
  • the first alkyl halide is CCl 4 , it reacts with the first metal element to generate graphite and a first metal halide; and/or, when the first alkyl halide is CCl 4 , it decomposes itself into graphite and chlorine.
  • the reduction reaction when step 1) is carried out in an electrolysis system, the reduction reaction also includes: the third metal halide obtains electrons to provide a first metal element and a second halogen ion; the first metal element reacts with the first hydrogen halide to generate a first hydrogen gas and a second metal halide.
  • step 1) when step 1) is performed in an electrolysis system, the reduction reaction further comprises: the first hydrogen halide obtains electrons to generate second hydrogen gas and third halogen ions.
  • step 1) when step 1) is carried out in an electrolysis system, it also includes a post-treatment step for the remaining part of the first alkyl halide and the remaining part of the first hydrogen halide, including: reacting the remaining part of the first alkyl halide with an alkaline substance to generate alcohol, aldehyde, carboxylic acid and a fourth metal halide.
  • the alkaline substance comprises a combination of one or more of an alkaline aqueous solution, an alkaline solid or an alkaline melt.
  • the alkaline aqueous solution is selected from conventional alkaline solutions such as lithium hydroxide aqueous solution, sodium hydroxide aqueous solution, potassium hydroxide aqueous solution, etc.
  • the alkaline solid is selected from conventional solids such as lithium hydroxide, sodium hydroxide, and potassium hydroxide.
  • the alkaline melt is selected from molten lithium hydroxide, molten sodium hydroxide, molten potassium hydroxide, etc.
  • the post-treatment step further comprises reacting the remaining portion of the first alkyl halide under the action of a catalyst to generate a second unsaturated hydrocarbon and a second hydrogen halide.
  • the catalyst is selected from a zeolite catalyst.
  • step 1) when step 1) is performed in an electrolysis system, the post-treatment step further comprises reacting the remaining portion of the first alkyl halide with the active metal to generate a third unsaturated hydrocarbon and a fifth metal halide.
  • the post-treatment step further includes recovering the remaining portion of the first alkyl halide and introducing it again for reaction to generate a first unsaturated hydrocarbon and a first metal halide.
  • step 1) when step 1) is performed in an electrolysis system, the post-treatment step further comprises reacting the remaining portion of the first hydrogen halide with the active metal to generate a sixth metal halide and a third hydrogen gas.
  • the illumination conditions are a wavelength of 200 to 450 nm and a reaction temperature of 20 to 600° C.
  • the heating conditions are above 250° C.
  • the hydrocarbon raw material gas reacts with the second halogen molecule to provide a second alkyl halide and a third hydrogen halide.
  • the second alkyl halide reacts with the active metal to provide a third unsaturated hydrocarbon and a fifth metal halide.
  • the third hydrogen halide reacts with the active metal to provide a sixth metal halide and a third hydrogen gas.
  • step 1) when step 1) is carried out under lighting conditions and/or heating conditions, it also includes a post-processing step: electrolyzing the fifth metal halide and/or the sixth metal halide to provide a second metal element and a second halogen gas, and recovering the second metal element for use in step 2) or step 3), and recovering the second halogen gas for use in step 1).
  • the second aspect of the present application provides an electrochemical device, comprising a reaction container, wherein the reaction container includes a metal halide molten salt unit; the metal halide molten salt unit is provided with an anode and a cathode; and also includes a vent pipe for supplying gas to the anode; the vent pipe is connected to the metal halide molten salt unit.
  • an air supply port is provided on the ventilation pipe.
  • an independent chamber is further included; the independent chamber is connected to the reaction container and is not in contact with the metal halide molten salt unit.
  • the ventilation pipe is sleeved on the anode; the cathode is sleeved on the ventilation pipe.
  • the cathode is disposed solely in the metal halide molten salt.
  • the anode is closer to the bottom of the reaction vessel than the vent pipe.
  • the material of the anode is selected from graphite.
  • the material of the cathode is selected from one of stainless steel, nickel, titanium, and nickel-based alloy.
  • the material of the reaction container is selected from alumina.
  • the ventilation tube is a ceramic insulated ventilation tube.
  • the third aspect of the present application provides the method for converting hydrocarbon feedstock and/or the use of the electrochemical device in preparing unsaturated hydrocarbons.
  • Active metals can react with alkyl halides and hydrogen halides to produce high-value products such as hydrogen, ethylene, acetylene, propylene, and graphite.
  • the generated metal halides are easy to separate and belong to different phases from the active metals.
  • the two are immiscible and have a density difference.
  • the separated metal halides can be regenerated into active metals and halogen gases through electrolysis and recycled to achieve a closed-loop process. Not only is the process simple and effective, but it also achieves resource recycling.
  • the reaction conditions are relatively milder. It does not require excessive pressure, and can be achieved at a relatively low pressure of 1 to 5 atmospheres, which is significantly lower than the 20 to 100 atmospheres of conventional methods.
  • the reaction temperature is relatively low, only about 200-600°C, which is significantly lower than the 850°C of conventional methods.
  • reaction process is simpler. It is not necessary to separate the sulfur-containing gas and carbon dioxide in the hydrocarbon raw material in advance, and the raw gas can be directly introduced into the system for conversion.
  • FIG. 1 is a schematic diagram showing a first partial structure of an electrochemical device of the present invention.
  • FIG. 2 is a schematic diagram showing a second partial structure of the electrochemical device of the present invention.
  • FIG. 3 is a schematic diagram showing a first overall structure of the electrochemical device of the present invention.
  • FIG. 4 is a schematic diagram showing a second overall structure of the electrochemical device of the present invention.
  • FIG. 5 shows the NMR spectrum of the output gas of Example 1 of the present invention.
  • FIG. 6 is a gas chromatogram showing hydrogen gas in the output gas of Example 1 of the present invention.
  • FIG. 7 is a gas chromatogram showing ethylene in the output gas of Example 1 of the present invention.
  • FIG. 8 is a gas chromatogram showing acetylene in the output gas of Example 1 of the present invention.
  • FIG. 9 shows the NMR spectrum of the output gas of Example 2 of the present invention.
  • FIG. 10 shows the NMR spectrum of the output gas of Example 3 of the present invention.
  • FIG. 11 shows the NMR spectrum of the output gas of Example 4 of the present invention.
  • FIG. 12 shows the NMR spectrum of the output gas of Example 5 of the present invention.
  • FIG. 13 shows the NMR spectrum of the output gas of Example 6 of the present invention.
  • FIG. 14 shows the NMR spectrum of the output gas of Example 7 of the present invention.
  • FIG. 15 shows the NMR spectrum of the output gas of Example 8 of the present invention.
  • FIG. 16 is a gas chromatogram showing hydrogen gas in the output gas of Example 9 of the present invention.
  • FIG. 17 is a gas chromatogram showing ethylene in the output gas of Example 9 of the present invention.
  • FIG. 18 is a gas chromatogram showing acetylene in the output gas of Example 9 of the present invention.
  • FIG. 19 is a gas chromatogram showing chloroform in Example 10 of the present invention.
  • FIG. 20 is a gas chromatogram showing ethylene in the reaction output gas at 400° C. according to Example 10 of the present invention.
  • FIG. 21 is a gas chromatogram showing acetylene in the reaction output gas at 400° C. according to Example 10 of the present invention.
  • FIG. 22 is a gas chromatogram showing ethylene in the reaction output gas at 500° C. according to Example 10 of the present invention.
  • FIG. 23 is a gas chromatogram showing acetylene in the reaction output gas at 500° C. according to Example 10 of the present invention.
  • FIG. 24 is a gas chromatogram showing dichloromethane in Example 11 of the present invention.
  • FIG. 25 is a gas chromatogram showing ethylene in the reaction output gas at 400° C. according to Example 11 of the present invention.
  • FIG. 26 is a gas chromatogram showing acetylene in the reaction output gas at 400° C. according to Example 11 of the present invention.
  • FIG. 27 is a gas chromatogram showing ethylene in the reaction output gas at 500° C. according to Example 11 of the present invention.
  • FIG. 28 is a gas chromatogram showing ethylene in the reaction output gas at 500° C. according to Example 12 of the present invention.
  • FIG. 29 is a gas chromatogram showing acetylene in the reaction output gas at 500° C. according to Example 12 of the present invention.
  • FIG. 30 shows the XRD characterization results of the silver bulk metal above the solidified salt of Example 1 of the present invention.
  • FIG. 31 shows the XRD characterization results of the black substance above the coagulation salt of Example 1 of the present invention.
  • range disclosed in this application is defined in the form of a lower limit and an upper limit, and a given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of the particular range.
  • the range defined in this way can be inclusive or exclusive of the end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a range. For example, if a range of 60 to 120 and 80 to 110 is listed for a specific parameter, it is understood that the range of 60 to 110 and 80 to 120 is also expected.
  • the numerical range "a to b" represents an abbreviation of any real number combination between a and b, where a and b are both real numbers.
  • the numerical range "0 to 5" means that all real numbers between "0 to 5" have been fully listed in this article, and "0 to 5" is just an abbreviation of these numerical combinations.
  • a parameter is expressed as an integer ⁇ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.
  • steps 1) and 2) which means that the method may include steps 1) and 2) performed sequentially, or may include steps 2) and 1) performed sequentially.
  • the first aspect of the present application provides a method for converting a hydrocarbon feedstock, comprising the following steps:
  • step 2) reacting the alkyl halide provided in step 1) with an active metal to generate a first unsaturated hydrocarbon and a first metal halide;
  • step 3 reacting the hydrogen halide provided in step 1) with an active metal to generate a second metal halide and hydrogen.
  • step 1) is carried out under a combination of one or more of the following conditions: electrolysis system, light irradiation, and heating.
  • the hydrocarbon feedstock gas is selected from a combination of one or more of methane, ethane, propane, and natural gas.
  • the hydrocarbon feedstock gas is selected from methane and/or ethane. More preferably, the hydrocarbon feedstock gas is selected from ethane.
  • the halogen substance includes a combination of one or more of halogen ions, halogen atoms, and halogen molecules.
  • the halogen atoms are selected from a combination of one or more of Cl, Br, and I;
  • the halogen ions include a first halogen ion;
  • the halogen molecules include a first halogen molecule and/or a second halogen molecule; more preferably, the first halogen ion is selected from a combination of one or more of Cl- , Br- , and I- ;
  • the first halogen molecule or the second halogen molecule is selected from a combination of one or more of Cl2 , Br2 , and I2 .
  • the alkyl halide includes a first alkyl halide and/or a second alkyl halide; the hydrogen halide includes a first hydrogen halide and/or a third hydrogen halide.
  • the first alkyl halide or the second alkyl halide can be, for example, a monoalkyl halide, a dialkyl halide, or a polyalkyl halide.
  • the monoalkyl halide can be, for example, a monoalkyl chloride, a monoalkyl bromide, or a monoalkyl iodide. Others will not be described one by one.
  • the first hydrogen halide or the third hydrogen halide is selected from hydrogen chloride, hydrogen bromide, hydrogen iodide and the like.
  • each first metal halide can be obtained from a specifically selected alkyl halide and a specifically selected active metal.
  • a monochloroalkane reacts with Na to obtain NaCl.
  • the explanation of the second metal halide is the same as above.
  • the active metal includes a metal element and/or a liquid alloy.
  • the metal element includes a first metal element.
  • the first metal element is selected from alkali metals and/or alkaline earth metals. More preferably, the first metal element is selected from a combination of one or more of Li, Na, K, Rb, Cs, Mg, Ca, Sr, and Ba.
  • Liquid alloy refers to a metal element dissolved in another low-melting-point metal.
  • the low-melting-point metal includes a combination of one or more of Ga, In, Sn, Pb, Zn, Bi, and Sb.
  • the hydrogen includes the first hydrogen and/or the third hydrogen.
  • the electrolysis system comprises an anode, a cathode and a metal halide molten salt.
  • the material of the anode is selected from graphite.
  • the material of the cathode is selected from a combination of one or more of stainless steel, nickel, titanium and nickel-based alloy.
  • the metal halide molten salt is selected from the melt of the third metal halide.
  • the molten body means that when the temperature reaches the melting point of the third metal halide, the third metal halide will reach a molten state.
  • the melting point is selected from 200 to 600°C; preferably 200 to 300°C, 300 to 400°C, 400 to 500°C, or 500 to 600°C, etc.
  • the metal halide molten salt provides a third metal halide in a molten state.
  • the third metal halide exists in an ionic state, and the third metal halide is used to provide a first metal ion and a first halogen ion as a metal halide molten salt electrolyte.
  • the first metal ion is selected from alkali metal ions and/or alkaline earth metal ions; more preferably, the first metal ion is selected from a combination of one or more of Li + , Na + , K + , Rb + , Cs + , Mg 2+ , Ca 2+ , Sr 2+ , and Ba 2+ .
  • step 1) when step 1) is carried out in an electrolysis system, one or more of the following two reactions occur at the anode:
  • the first halogen ions undergo an oxidation reaction at the anode to provide first halogen molecules
  • the hydrocarbon raw material gas and the first halogen molecules undergo an oxidation reaction at the anode to provide first alkyl halide and first hydrogen halide.
  • the generated first alkyl halide may be methyl chloride and the first hydrogen halide is hydrogen chloride.
  • the first halogen ion undergoes an oxidation reaction with the hydrocarbon feedstock at the anode to provide a first alkyl halide and a first hydrogen halide.
  • the generated first alkyl halide may be methyl chloride and the first hydrogen halide is hydrogen chloride.
  • the first hydrogen halide and the first alkyl halide generated by the anode reaction are mostly present in the form of gas. At least part of the first alkyl halide and at least part of the first hydrogen halide can diffuse to the cathode for reduction reaction. During the gas diffusion process, the hydrocarbon raw material gas that has not been converted in the anode can also continue to react with the first halogen ions or the first halogen molecules to generate more first alkyl halide and the first hydrogen halide.
  • the third metal halide is selected from a combination of one or more of metal chlorides, metal bromides, and metal iodides. More preferably, the metal chloride is selected from a combination of one or more of LiCl, NaCl, KCl, RbCl, CsCl, MgCl 2 , CaCl 2 , SrCl 2 , BaCl 2 , and ZnCl 2.
  • the metal bromide is selected from a combination of one or more of LiBr, NaBr, KBr, RbBr, CsBr, MgBr 2 , CaBr 2 , SrBr 2 , BaBr 2 , and ZnBr 2.
  • the metal iodide is selected from a combination of one or more of LiI, NaI, KI, RbI, CsI, MgI 2 , CaI 2 , SrI 2 , BaI 2 , and ZnI 2 .
  • step 1) when step 1) is carried out in an electrolysis system, for a unit volume of 1 cm 3 of metal halide molten salt, the flow rate of the hydrocarbon feedstock gas is 0.02 to 0.8 cm 3 /min.
  • the gas flow rate of the gas supply port is 0.072 cm 3 /min.
  • the gas flow rate is limited to make the amount of hydrocarbon raw material gas close to the amount of the first halogen molecular gas generated at the anode. If the amount of hydrocarbon raw material gas is much smaller than the amount of the first halogen molecular gas generated at the anode, then the excess first halogen molecular gas that has not reacted with the hydrocarbon raw material will float to the cathode, consuming the first metal element and the first hydrogen generated at the cathode, thereby reducing the amount of high-value products generated; if the hydrocarbon raw material gas flow rate is too high, it will reduce the retention time of the hydrocarbon raw material gas in the reactor, thereby reducing the conversion rate.
  • the reaction temperature of the electrolyte system is 200-600°C, preferably 200-300°C, 300-400°C, 400-500°C, or 500-600°C.
  • the reaction voltage of the electrolyte system is 3-10V, preferably 3-4V, 4-5V, 5-8V, or 8-10V.
  • step 1) when step 1) is carried out in an electrolysis system, the reduction reaction includes the following three situations:
  • the third metal halide obtains electrons to provide the first metal element and the second halogen ion; the first metal element reacts with the first alkyl halide to generate the first unsaturated hydrocarbon and the first metal halide.
  • the first unsaturated hydrocarbon may be, for example, an olefin or an alkyne.
  • An olefin may be, for example, ethylene, propylene, etc.
  • An alkyne may be, for example, acetylene, propyne, etc.
  • the graphite may be located at the bottom of the third metal halide, or float above the third metal halide, or be mixed in the interior of the third metal halide, depending on the density of the graphite and the third metal halide, the viscosity of the third metal halide, and the ventilation conditions.
  • the third metal halide obtains electrons to provide a first metal element and a second halogen ion; the first metal element reacts with the first hydrogen halide to generate a first hydrogen gas and a second metal halide.
  • the second halogen ion is selected from a combination of one or more of Cl - , Br - , and I - .
  • the first hydrogen halide obtains electrons to generate second hydrogen gas and third halogen ions.
  • the third halogen ions are selected from a combination of one or more of Cl - , Br - , and I - .
  • step 1) when step 1) is carried out in an electrolysis system, it also includes a post-treatment step of the remaining portion of the first alkyl halide and the remaining portion of the first hydrogen halide, including one or more combinations of the following five methods:
  • the alkaline substance includes a combination of one or more of an alkaline aqueous solution, an alkaline solid or an alkaline melt.
  • the alkaline aqueous solution is selected from conventional alkaline solutions such as lithium hydroxide aqueous solution, sodium hydroxide aqueous solution, and potassium hydroxide aqueous solution.
  • the alkaline solid is selected from conventional solids such as lithium hydroxide, sodium hydroxide, and potassium hydroxide.
  • the alkaline melt is selected from molten lithium hydroxide, molten sodium hydroxide, and molten potassium hydroxide.
  • the fourth metal halide is selected from a combination of one or more of metal chlorides, metal bromides, and metal iodides. More preferably, the metal chloride is selected from a combination of one or more of LiCl, NaCl, KCl, RbCl, CsCl, MgCl 2 , CaCl 2 , SrCl 2 , BaCl 2 , and ZnCl 2 .
  • the metal bromide is selected from one or more combinations of LiBr, NaBr, KBr, RbBr, CsBr, MgBr2 , CaBr2 , SrBr2 , BaBr2 , and ZnBr2 .
  • the metal iodide is selected from one or more combinations of LiI, NaI, KI, RbI, CsI, MgI2 , CaI2 , SrI2 , BaI2 , and ZnI2 .
  • the catalyst is selected from a zeolite catalyst.
  • the second unsaturated hydrocarbon can be, for example, an olefin or an alkyne.
  • the olefin can be, for example, ethylene, propylene, etc.
  • the alkyne can be, for example, acetylene, propyne, etc.
  • the second hydrogen halide is selected from hydrogen chloride, hydrogen bromide, hydrogen iodide, etc.
  • the third unsaturated hydrocarbon may be, for example, an olefin or an alkyne.
  • the olefin may be, for example, ethylene, propylene, etc.
  • the alkyne may be, for example, acetylene, propyne, etc.
  • the fifth metal halide is selected from a combination of one or more of metal chlorides, metal bromides, and metal iodides.
  • the metal chloride is selected from a combination of one or more of LiCl, NaCl, KCl, RbCl, CsCl, MgCl 2 , CaCl 2 , SrCl 2 , BaCl 2 , and ZnCl 2.
  • the metal bromide is selected from a combination of one or more of LiBr, NaBr, KBr, RbBr, CsBr, MgBr 2 , CaBr 2 , SrBr 2 , BaBr 2 , and ZnBr 2 .
  • the metal iodide is selected from one or more combinations of LiI, NaI, KI, RbI, CsI, MgI 2 , CaI 2 , SrI 2 , BaI 2 , and ZnI 2 , as shown in Examples 10 to 12 of the present application.
  • the illumination conditions are wavelengths of 200 to 450 nm; preferably 200 to 250 nm, 250 to 350 nm, or 350 to 450 nm, etc.
  • the reaction temperature of the illumination conditions is 20 to 600° C.; preferably 20 to 100° C., 100 to 200° C., or 200 to 600° C., etc.
  • the heating conditions are above 250° C.
  • the hydrocarbon feedstock gas reacts with the second halogen molecule gas to provide a second alkyl halide and a third hydrogen halide.
  • the second alkyl halide reacts with an active metal to provide a third unsaturated hydrocarbon and a fifth metal halide.
  • the third hydrogen halide reacts with the active metal to provide a sixth metal halide and a third hydrogen gas.
  • the sixth metal halide is selected from a combination of one or more of metal chlorides, metal bromides, and metal iodides. More preferably, the metal chloride is selected from a combination of one or more of LiCl, NaCl, KCl, RbCl, CsCl, MgCl 2 , CaCl 2 , SrCl 2 , BaCl 2 , and ZnCl 2.
  • the metal bromide is selected from a combination of one or more of LiBr, NaBr, KBr, RbBr, CsBr, MgBr 2 , CaBr 2 , SrBr 2 , BaBr 2 , and ZnBr 2.
  • the metal iodide is selected from a combination of one or more of LiI, NaI, KI, RbI, CsI, MgI 2 , CaI 2 , SrI 2 , BaI 2 , and ZnI 2 .
  • a post-processing step is further included: electrolyzing the fifth metal halide and/or the sixth metal halide to provide a second metal element and a second halogen molecular gas, and recovering the second metal element for use in step 2) or step 3), and recovering the second halogen molecular gas for use in step 1).
  • the second metal element is selected from a combination of one or more of Li, Na, K, Rb, Cs, Mg, Ca, Sr, and Ba.
  • the present application provides an electrochemical device, including a reaction vessel 1, wherein the reaction vessel 1 includes a metal halide molten salt unit 4.
  • the metal halide molten salt unit 4 is provided with an anode 3 and a cathode 2. It also includes a vent pipe 5 for supplying gas to the anode 3.
  • the vent pipe 5 is connected to the metal halide molten salt unit 4.
  • a gas supply port 6 is provided on the vent pipe 5.
  • the gas of the gas supply port 6 is selected from hydrocarbon raw gas.
  • the hydrocarbon raw gas is selected from a combination of one or more of methane, ethane, propane, and natural gas.
  • the hydrocarbon raw gas is selected from methane and/or ethane. More preferably, the hydrocarbon raw gas is selected from ethane.
  • the material of the metal halide molten salt unit 4 is selected from metal halide molten salt.
  • the metal halide molten salt is selected from a melt of a third metal halide.
  • the third metal halide is selected from one or more of LiCl, NaCl, KCl, RbCl, CsCl, MgCl 2 , CaCl 2 , SrCl 2 , BaCl 2 , ZnCl 2 , LiBr, NaBr, KBr, RbBr, CsBr, MgBr 2 , CaBr 2 , SrBr 2 , BaBr 2 , ZnBr 2 , LiI , NaI, KI, RbI, CsI, MgI 2 , CaI 2 , SrI 2 , BaI 2 , and ZnI 2 .
  • the material of the anode 3 is selected from graphite.
  • the material of the cathode 2 is selected from one of stainless steel, nickel, titanium, and nickel-based alloy.
  • the material of the reaction container 1 is selected from alumina.
  • the height of the reaction container 1 is 30 to 60 cm.
  • the ventilation pipe 5 is a ceramic insulating ventilation pipe.
  • the anode 3 is closer to the bottom of the reaction vessel 1 than the vent pipe 5, so as to ensure that the anode 3 extends out of the vent pipe 5 so as to be in contact with the metal halide molten salt unit 4.
  • the length of the anode 3 immersed in the metal halide molten salt unit 4 is 10 to 15 cm.
  • the length of the vent pipe 5 immersed in the metal halide molten salt unit 4 is 7 to 12 cm.
  • the length of the cathode 2 immersed in the metal halide molten salt unit 4 is 4 to 9 cm.
  • the vent pipe 5 is sleeved on the anode 3.
  • the cathode 2 can be sleeved outside the vent pipe 5, in which case the vent pipe 5 is closer to the bottom of the reaction vessel 1 than the cathode 2, so that the vent pipe 5 can be in contact with the metal halide molten salt unit 4, so that it can be formed in the metal halide molten salt unit 4, from long to short: anode 3> vent pipe 5> cathode 2.
  • the cathode 2 can also be separated from the vent pipe 5 and separately arranged in the metal halide molten salt unit 4.
  • the anode 3 can be closer to the bottom of the reaction vessel 1 than the cathode 2, or it can be flush with the cathode 2, or it can be farther away from the bottom of the reaction vessel 1 than the cathode 2.
  • the electrochemical device provided in the present application also includes an independent chamber 7.
  • the independent chamber 7 is connected to the reaction vessel 1 and is not in contact with the metal halide molten salt unit 4.
  • An active metal is provided in the independent chamber 7.
  • the active metal includes a metal element and/or a liquid alloy.
  • the metal element includes a combination of one or more of Li, Na, K, Rb, Cs, Mg, Ca, Sr, and Ba.
  • the liquid alloy refers to the metal element melted in another low-melting-point metal, and the low-melting-point metal includes a combination of one or more of Ga, In, Sn, Pb, Zn, Bi, and Sb.
  • the low-melting-point metal does not react, and its function is to form a liquid alloy, and the liquid alloy is less corrosive to the independent chamber 7.
  • the independent chamber 7 is arranged inside the reaction vessel 1, for example, it can be arranged at the top.
  • the independent chamber 7 is arranged outside the reaction vessel.
  • the electrochemical device provided in the present application operates under the conditions of applied voltage and temperature.
  • the voltage is 3 to 10 V; preferably 3 to 4 V, 4 to 5 V, 5 to 8 V, or 8 to 10 V.
  • the temperature is 200 to 600 ° C; preferably 200 to 300 ° C, 300 to 400 ° C, 400 to 500 ° C, or 500 to 600 ° C.
  • hydrocarbon raw gas is introduced into the gas supply port 6, an oxidation reaction occurs at the anode 3, and the hydrocarbon raw gas reacts with the halogen ions provided by the metal halide molten salt unit 4 to generate a first alkyl halide and a first hydrogen halide.
  • At least a portion of the first alkyl halide and at least a portion of the first hydrogen halide diffuse to the cathode 2, and a reduction reaction occurs to provide a combination of one or more of the first hydrogen gas, the second halogen ion, the first unsaturated hydrocarbon and the second metal halide.
  • the remaining portion of the first halogenated hydrocarbon and the remaining portion of the first hydrogen halide generated by the anode 3 float to the independent chamber 7 and react with the active metal to generate a third unsaturated hydrocarbon, a fifth metal halide, a sixth metal halide and a third hydrogen.
  • a third unsaturated hydrocarbon and a fifth metal halide are generated.
  • a sixth metal halide and a third hydrogen are generated.
  • the hydrocarbon raw material gas can also react with the second halogen molecule gas in an independent chamber to generate a second alkyl halide and a third hydrogen halide.
  • the second alkyl halide can react with an active metal to generate a third unsaturated hydrocarbon and a fifth metal halide.
  • the third hydrogen halide can react with an active metal to generate a sixth metal halide and a third hydrogen.
  • the third unsaturated hydrocarbon can be generated from the above two pathways, thereby further increasing the total amount of unsaturated hydrocarbons generated.
  • the generated fifth metal halide and sixth metal halide can float to the surface of the liquid alloy, are not miscible, and are easy to separate the metal halide and reuse as the metal halide molten salt unit 4 for the electrochemical reaction.
  • Another aspect of the present application provides the method for converting hydrocarbon raw materials and/or the use of the electrochemical device in preparing unsaturated hydrocarbons.
  • Unsaturated hydrocarbons can be used as chemical raw materials and have high industrial value.
  • alumina reaction vessel with an inner diameter of 22mm and a capped end. Place the alumina reaction vessel in a high-temperature tube furnace. At a temperature of 500°C, the salt melts to form a molten salt with a height of about 10cm.
  • a graphite anode (diameter: 3mm) is inserted into the bottom of the molten salt electrolyte. The outside of the graphite anode is surrounded by a ceramic insulating vent tube made of alumina. The graphite anode extends out of the ceramic insulating vent tube by about 3cm.
  • the cathode is a stainless steel tube inserted into the salt electrolyte by about 4cm. The stainless steel tube cathode is sleeved on the outside of the ceramic insulating vent tube.
  • the composition of the exhaust gas was analyzed using a gas chromatograph (GC), and it was found that in the fifth hour of electrolysis, the conversion rate of methane reached 60%, and the outputs of hydrogen, ethylene and acetylene were 3 cm 3 /min, 0.035 cm 3 /min and 0.14 cm 3 /min, respectively.
  • the GC signals of hydrogen, ethylene and acetylene are shown in Figures 6, 7 and 8, respectively.
  • the above results show that in the electrochemical system containing LiCl-NaCl-KCl molten salt electrolyte, under the conditions of 500°C and 6V voltage, methane is effectively activated, and the yields of hydrogen, ethylene and acetylene are high. After the experiment, the reactor was opened.
  • the metal chloride molten electrolyte will become a solidified salt at room temperature.
  • Silver block metal was found above the solidified salt.
  • Samples were taken and characterized by XRD. The results are shown in Figure 30, indicating that the main phase of the sample is metallic sodium, which indicates that metallic sodium is generated at the cathode during the electrolysis process.
  • black matter was found above the solidified salt. It was characterized by Raman spectrometer. The results are shown in Figure 31. The characteristic peaks of graphite were found at Raman shifts of 1360cm -1 and 1590cm -1 , which indicates that during the reaction, part of the methane can be converted into tetrachloromethane, and then high-value graphite is generated.
  • the graphite anode extends out of the ceramic insulating vent tube by about 3cm.
  • the cathode is a stainless steel tube inserted into the salt electrolyte by about 9cm.
  • the stainless steel tube cathode is sleeved on the outside of the ceramic insulating vent tube.
  • the composition of the exhaust gas was analyzed using a gas chromatograph, and it was found that at the 4.5th hour of electrolysis, the conversion rate of methane reached 40%, and the outputs of hydrogen, ethylene and acetylene were 2.5 cm 3 /min, 0.05 cm 3 /min and 0.07 cm 3 /min, respectively.
  • the above results show that in an electrochemical system containing a LiCl-NaCl-KCl molten salt electrolyte, methane is effectively activated at 600°C and a constant current of 0.75A is applied, and the yields of hydrogen, ethylene and acetylene are high.
  • the reactor is opened and the metal chloride molten electrolyte will turn into solidified salt at room temperature. Graphite is found above the solidified salt.
  • the graphite anode extends out of the ceramic insulating vent tube by about 3cm.
  • the cathode is a stainless steel tube, which is inserted into the salt electrolyte by about 4cm.
  • the stainless steel tube cathode is sleeved on the outside of the ceramic insulating vent tube.
  • alumina reaction vessel with an inner diameter of 22mm and a capped end. Place the alumina reaction vessel in a high-temperature tube furnace. At a temperature of 450°C, the salt melts to form a molten salt with a height of about 10cm.
  • a graphite anode (diameter: 3mm) is inserted into the bottom of the molten salt electrolyte. The outside of the graphite anode is surrounded by a ceramic insulating vent tube made of alumina. The graphite anode extends out of the ceramic insulating vent tube by about 3cm.
  • the cathode is a stainless steel tube inserted into the salt electrolyte by about 4cm. The stainless steel tube cathode is sleeved on the outside of the ceramic insulating vent tube.
  • Methane was used as a hydrocarbon raw material with a flow rate of 3 cm3 /min; nitrogen was used as a carrier gas with a flow rate of 17 cm3/min.
  • a voltage of 6V was applied, and the output gas was collected using deuterated chloroform solvent and analyzed using nuclear magnetic resonance. As shown in Figure 11, an obvious signal of dichloromethane was found, proving the effective activation of methane at the anode.
  • the composition of the exhaust gas was analyzed using a gas chromatograph, and it was found that at the 3rd hour and 40 minutes of electrolysis, the conversion rate of methane reached 50%, the yield of hydrogen was about 1 cm3 /min, and a small amount of ethylene and acetylene was generated.
  • the above results show that in an electrochemical system containing a LiCl-KCl molten salt electrolyte, methane is effectively activated at 450°C and a voltage of 6V is applied to generate hydrogen, ethylene and acetylene.
  • the graphite anode extends out of the ceramic insulating vent tube by about 3cm.
  • the cathode is a stainless steel tube inserted into the salt electrolyte by about 4cm.
  • the stainless steel tube cathode is sleeved on the outside of the ceramic insulating vent tube.
  • a mixture of methane and nitrogen is passed to the anode surface through a ceramic insulated vent pipe.
  • Methane is used as a hydrocarbon raw material with a flow rate of 3 cm 3 /min; nitrogen is used as a carrier gas with a flow rate of 17 cm 3 /min.
  • a voltage of 6V is applied, and the output gas is collected using deuterated chloroform solvent and analyzed using nuclear magnetic resonance. As shown in Figure 12, it is found that the signal of dichloromethane is stronger than that at 450°C, which proves the effective activation of methane at the anode. Increasing the temperature is conducive to the generation of dichloromethane.
  • the composition of the exhaust gas was analyzed using a gas chromatograph.
  • the methane conversion rate was approximately 80% and relatively stable, and the hydrogen production was approximately 1 ml/min.
  • the production of ethylene and acetylene increased significantly, with acetylene reaching a maximum of 0.012 ml/min and ethylene reaching a maximum of 0.002 ml/min.
  • the graphite anode extends out of the ceramic insulating vent tube by about 3cm.
  • the cathode is a stainless steel tube, which is inserted into the salt electrolyte by about 4cm.
  • the stainless steel tube cathode is sleeved on the outside of the ceramic insulating vent tube.
  • a mixture of methane and nitrogen was passed to the anode surface through a ceramic insulated vent pipe.
  • Methane was used as the hydrocarbon raw material with a flow rate of 3 cm 3 /min; argon was used as the carrier gas with a flow rate of 17 cm 3 /min.
  • a constant current of 1A was applied, and the output gas was collected using DMSO solvent and analyzed using nuclear magnetic resonance. As shown in Figure 13, a signal of methyl chloride appeared, proving the effective activation of methane at the anode.
  • the graphite anode extends out of the ceramic insulating vent tube by about 3cm.
  • the cathode is a stainless steel tube, which is inserted into the salt electrolyte by about 4cm.
  • the stainless steel tube cathode is sleeved on the outside of the ceramic insulating vent tube.
  • the graphite anode extends out of the ceramic insulating vent tube by about 3cm.
  • the cathode is a stainless steel tube, which is inserted into the salt electrolyte by about 4cm.
  • the stainless steel tube cathode is sleeved on the outside of the ceramic insulating vent tube.
  • the composition of the exhaust gas was analyzed by gas chromatograph, and it was found that in the 5th hour of electrolysis, the conversion rate of methane reached about 55%, and the production rate of H 2 was 0.32 cm 3 /min.
  • the above results show that in the electrochemical system containing LiBr-NaBr-KBr molten salt electrolyte, methane was effectively activated to generate hydrogen at 500°C and 1A current was applied.
  • the graphite anode extends out of the ceramic insulating vent tube by about 3cm.
  • the cathode is a stainless steel tube, which is inserted into the salt electrolyte by about 4cm.
  • the stainless steel tube cathode is sleeved on the outside of the ceramic insulating vent tube.
  • a mixture of ethane and argon is passed to the anode surface through a ceramic insulated vent pipe.
  • Ethane is used as a hydrocarbon raw material with a flow rate of 3 cm 3 /min; argon is used as a carrier gas with a flow rate of 17 cm 3 /min.
  • a constant current of 1A is applied, and a high-precision gas chromatograph is used to analyze the composition of the exhaust gas.
  • the conversion rate of ethane is always close to 100%, and the production of hydrogen and ethylene gradually increases with the electrolysis time.
  • the hydrogen production rate is about 3 cm 3 /min
  • the ethylene production rate is about 1 cm 3 /min
  • the selectivity of ethylene reaches 25%
  • the acetylene production rate is about 0.25 cm 3 /min.
  • the high-precision GC signals of hydrogen, ethylene and acetylene in the gas products at the 7.5th hour of electrolysis are shown in Figures 16, 17 and 18, respectively.
  • the above results show that in the electrochemical system containing LiCl-NaCl-KCl molten salt electrolyte, at 500°C and with an applied current of 1A, ethane is nearly 100% activated, generating a large amount of hydrogen, ethylene and acetylene.
  • 1g of sodium metal was weighed and placed in an alumina porcelain boat, and then transferred together to a quartz tube with an inner diameter of 42mm, and the temperature was programmed to 400°C or 500°C in argon (flow rate of 17cm3 /min), and then the argon gas flow (flow rate maintained at 17cm3 /min) was passed through a gas washing bottle filled with 5cm high liquid chloroform, carrying out a certain amount of chloroform at room temperature and flowing into the reaction system, reacting with sodium metal at high temperature, and then the reacted gas was passed into a high-precision gas chromatograph to characterize its composition.
  • the gas after the reaction of sodium metal and chloroform at 400°C contained ethylene and acetylene, as shown in Figures 20 and 21, respectively.
  • the gas after the reaction of chloroform and sodium metal at 500°C also contained ethylene and acetylene, as shown in Figures 22 and 23, respectively.
  • This embodiment indirectly verifies that the sodium metal generated by the cathode reaction in the electrochemical experiment can react with the chloroform generated at the anode to generate ethylene and acetylene.
  • this embodiment also illustrates that the chloroform produced in the anode of the electrochemical system, if not completely reacted, can react with an active metal (such as sodium) to generate unsaturated hydrocarbons.
  • 1g of sodium metal was weighed and placed in an alumina porcelain boat, and then transferred together into a quartz tube with an inner diameter of 42mm.
  • the temperature was programmed to 400°C or 500°C in argon (flow rate of 17cm3 /min), and then the argon gas flow (flow rate maintained at 17cm3 /min) was passed through a gas washing bottle filled with 5cm high liquid dichloromethane, carrying a certain amount of dichloromethane at room temperature and flowing into the reaction system, reacting with sodium metal at high temperature, and then the reacted gas was passed into a high-precision gas chromatograph to characterize its composition.
  • the gas after the reaction of sodium metal and dichloromethane at 400°C contains ethylene and acetylene, as shown in Figures 25 and 26, respectively.
  • the gas product of the reaction of dichloromethane and sodium metal at 500°C is mainly ethylene.
  • Figure 27 is a gas chromatogram of ethylene. This embodiment indirectly verifies that the sodium metal generated by the cathode reaction in the electrochemical experiment can react with the dichloromethane generated at the anode to generate ethylene.
  • this embodiment also illustrates that the dichloromethane produced in the anode of the electrochemical system, if not completely reacted, can react with an active metal (such as sodium) to generate unsaturated hydrocarbons.

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Abstract

本申请涉及烃类原料转化领域，具体地，涉及一种烃类原料高效转化的方法及其装置。所述方法包括以下步骤：1)将烃类原料气体与卤素物质反应生成卤代烷和卤化氢；2)将步骤1)提供的卤代烷与活泼金属反应，生成第一不饱和烃和第一金属卤化物；3)将步骤1)提供的卤化氢与活泼金属反应，生成第二金属卤化物和氢气。本申请在电化学体系中，可以将烃类原料气体转化为氢气、乙烯、乙炔、丙烯、石墨等高价值产物。

Description

一种烃类原料高效转化的方法及其装置 技术领域
本申请涉及烃类原料转化领域，具体地，涉及一种烃类原料高效转化的方法及其装置。
背景技术
天然气在地球上储量丰富，在全球能源格局中占有重要地位。天然气的主要成分是甲烷，其次是乙烷和丙烷。目前，天然气的主要用途是作为燃料供热。相比之下，仅有不到10％的天然气用作化工原料。由于页岩气、煤层气、深海可燃冰中天然气储量巨大，以天然气为化工原料生产高价值产物的技术具有重要环保和经济意义。
因为甲烷分子的碳氢键稳定而且结构对称，所以甲烷的高效转化是一个挑战。工业上的甲烷湿重整制氢工艺往往需要超过800℃的反应条件，这使得该反应的能耗较大，运行成本高，而且该过程还排放大量的二氧化碳温室气体。已有专利公开了一种将烃类原料(包括甲烷)转化为较不饱和烃的方法，具体包括以下几个独立步骤：(1)将烃原料卤化形成卤代烷、(2)再使卤代烷转化为不饱和烃和卤化氢，(3)然后再将不饱和烃从卤化烃分离，(4)然后再在水性介质或气相中电解卤化氢为氢和分子卤素。虽然该过程可以通过重复以上步骤实现连续生产，但是它流程复杂，涉及多个独立步骤和反应腔室，成本高，因而较难实现大规模化运行。此外，工业上从烃类原料制备乙烯、丙烯和丁二烯等不饱和烃的蒸汽热裂解法通常在超过850℃和超高压下运行，能耗巨大。在全球范围内，蒸汽热裂解过程每年排放超过3亿吨二氧化碳温室气体。综上所述，寻找高效、简单、低成本、低能耗、低排放和易于规模化的烃类原料转化工艺非常重要。
发明内容
鉴于以上所述现有技术的缺点，为解决现有技术中烃类原料在温和条件下高效转化的技术挑战，本申请的目的在于提供一种烃类原料转化的方法及其装置，用于解决现有技术的问题。
为实现上述目的及其他相关目的，本申请第一方面提供一种烃类原料转化的方法，包括以下步骤：
1)将烃类原料气体与卤素物质反应生成卤代烷和卤化氢；
2)将步骤1)提供的卤代烷与活泼金属反应，生成第一不饱和烃和第一金属卤化物；
3)将步骤1)提供的卤化氢与活泼金属反应，生成第二金属卤化物和氢气。
在本申请的任意实施例中，步骤1)是在电解体系、光照、加热条件中的一种或多种的 组合情况下进行。
在本申请的任意实施例中，步骤1)中，所述烃类原料气体选自甲烷、乙烷、丙烷、天然气中的一种或多种的组合。优选地，所述烃类原料气体选自甲烷和/或乙烷。更优选地，所述烃类原料气体选自乙烷。
在本申请的任意实施例中，步骤1)中，所述卤素物质包括卤素离子、卤素原子、卤素分子中的一种或多种的组合。优选地，所述卤素原子选自Cl、Br、I中的一种或多种的组合。所述卤素离子包括第一卤素离子。卤素分子包括第一卤素分子和/或第二卤素分子。更优选地，所述卤素离子选自Cl -、Br -、I -中的一种或多种的组合。所述卤素分子选自Cl 2、Br 2、I 2中的一种或多种的组合。
在本申请的任意实施例中，步骤1)中，所述卤代烷包括第一卤代烷和/或第二卤代烷；所述卤化氢包括第一卤化氢和/或第三卤化氢。
在本申请的任意实施例中，步骤2)或步骤3)中，所述活泼金属包括金属单质和/或液态合金。液态合金是指将金属单质溶于另一种低熔点的金属获得。优选地，低熔点的金属选自Ga、In、Sn、Pb、Zn、Bi、Sb中的一种或多种的组合。金属单质包括第一金属单质。优选地，所述第一金属单质选自碱金属和/或碱土金属。更优选地，所述第一金属单质选自Li、Na、K、Rb、Cs、Mg、Ca、Sr、Ba中的一种或多种的组合。
在本申请的任意实施例中，步骤3)中，所述氢气包括第一氢气和/或第三氢气。
在本申请的任意实施例中，当步骤1)在电解体系中进行时，所述电解体系包括阳极、阴极和金属卤化物熔融盐。金属卤化物熔融盐在熔融状态下提供第三金属卤化物，第三金属卤化物用于提供第一金属离子和第一卤素离子，第一金属离子在阴极发生还原反应以提供第一金属单质。
在本申请的任意实施例中，当步骤1)在电解体系中进行时，第一卤素离子在阳极发生氧化反应以提供第一卤素分子，所述烃类原料气体与第一卤素分子在阳极发生氧化反应，以提供第一卤代烷和第一卤化氢。
和/或，第一卤素离子与所述烃类原料气体在阳极发生氧化反应，以提供第一卤代烷和第一卤化氢。
优选地，至少部分的所述第一卤代烷和至少部分的所述第一卤化氢扩散到阴极发生还原反应生成第一氢气、第二卤素离子、第一不饱和烃和第二金属卤化物中的一种或多种的组合。
在本申请的任意实施例中，当步骤1)在电解体系中进行时，所述金属卤化物熔融盐选自第三金属卤化物的熔融体。优选地，所述第三金属卤化物选自金属氯化物、金属溴化物、 金属碘化物中的一种或多种的组合。更优选地，所述金属氯化物选自LiCl、NaCl、KCl、RbCl、CsCl、MgCl 2、CaCl 2、SrCl 2、BaCl 2、ZnCl 2中的一种或多种的组合。所述金属溴化物选自LiBr、NaBr、KBr、RbBr、CsBr、MgBr 2、CaBr 2、SrBr 2、BaBr 2、ZnBr 2中的一种或多种的组合。所述金属碘化物选自LiI、NaI、KI、RbI、CsI、MgI 2、CaI 2、SrI 2、BaI 2、ZnI 2中的一种或多种的组合。
在本申请的任意实施例中，当步骤1)在电解体系中进行时，对于单位体积1cm 3的金属卤化物熔融盐，通入所述烃类原料气体的流速为0.02～0.8cm 3/min。
在本申请的任意实施例中，当步骤1)在电解体系中进行时，所述电解质体系的反应温度为200～600℃。所述电解质体系的反应电压为3～10V。
在本申请的任意实施例中，当步骤1)在电解体系中进行时，所述还原反应包括：所述第三金属卤化物得电子以提供第一金属单质和第二卤素离子；所述第一金属单质与所述第一卤代烷反应生成第一不饱和烃和第一金属卤化物。当所述第一卤代烷为CCl 4时，与所述第一金属单质会反应生成石墨和第一金属卤化物；和/或，当所述第一卤代烷为CCl 4时，自身分解成石墨和氯气。
在本申请的任意实施例中，当步骤1)在电解体系中进行时，所述还原反应还包括：所述第三金属卤化物得电子以提供第一金属单质和第二卤素离子；所述第一金属单质与所述的第一卤化氢反应生成第一氢气和第二金属卤化物。
在本申请的任意实施例中，当步骤1)在电解体系中进行时，所述还原反应还包括：所述第一卤化氢得电子生成第二氢气和第三卤素离子。
在本申请的任意实施例中，当步骤1)在电解体系中进行时，还包括对剩余部分的所述第一卤代烷和剩余部分的所述第一卤化氢的后处理步骤，包括：将剩余部分的所述第一卤代烷与碱性物质反应生成醇、醛、羧酸和第四金属卤化物。优选地，所述碱性物质包括碱水溶液、碱性固体或碱性熔融体中的一种或多种的组合。更优选地，碱水溶液选自氢氧化锂水溶液、氢氧化钠水溶液、氢氧化钾水溶液等常规碱性溶液。碱性固体选自氢氧化锂、氢氧化钠、氢氧化钾中等常规固体。碱性熔融体选自熔融氢氧化锂、熔融氢氧化钠、熔融氢氧化钾等。
在本申请的任意实施例中，当步骤1)在电解体系中进行时，所述后处理步骤还包括将剩余部分的所述第一卤代烷在催化剂的作用下反应生成第二不饱和烃和第二卤化氢。所述催化剂选自沸石催化剂。
在本申请的任意实施例中，当步骤1)在电解体系中进行时，所述后处理步骤还包括将剩余部分的所述第一卤代烷与所述活泼金属反应生成第三不饱和烃和第五金属卤化物。
在本申请的任意实施例中，当步骤1)在电解体系中进行时，所述后处理步骤还包括将剩余部分的所述第一卤代烷回收，再次通入进行反应，生成第一不饱和烃和第一金属卤化物。
在本申请的任意实施例中，当步骤1)在电解体系中进行时，所述后处理步骤还包括将剩余部分的所述第一卤化氢与所述活泼金属反应生成第六金属卤化物和第三氢气。
在本申请的任意实施例中，当步骤1)在光照条件和/或加热条件下进行时，所述光照条件是波长为200～450nm，反应温度为20～600℃。所述加热条件是在250℃以上。在所述光照条件和/或加热条件下，所述烃类原料气体与第二卤素分子反应以提供第二卤代烷和第三卤化氢。第二卤代烷与所述活泼金属反应以提供第三不饱和烃和第五金属卤化物。第三卤化氢与所述活泼金属反应以提供第六金属卤化物和第三氢气。
在本申请的任意实施例中，当步骤1)在光照条件和/或加热条件下进行时，还包括后处理步骤：将第五金属卤化物和/或第六金属卤化物电解以提供第二金属单质和第二卤素气体，并回收第二金属单质用于步骤2)或步骤3)中，回收第二卤素气体用于步骤1)中。
本申请第二方面提供一种电化学装置，包括反应容器，所述反应容器中包括金属卤化物熔融盐单元；所述金属卤化物熔融盐单元中设有阳极和阴极；还包括用于给阳极供气的通气管；所述通气管与金属卤化物熔融盐单元连通。
在本申请的任意实施例中，所述通气管上设有供气口。
在本申请的任意实施例中，还包括独立腔室；所述独立腔室与所述反应容器相连，且不与所述金属卤化物熔融盐单元接触。
在本申请的任意实施例中，所述通气管套设于所述阳极；所述阴极套设于所述通气管。
在本申请的任意实施例中，所述阴极单独设于所述金属卤化物熔融盐中。
在本申请的任意实施例中，所述阳极比通气管更靠近所述反应容器的底部。
在本申请的任意实施例中，所述阳极的材质选自石墨。
在本申请的任意实施例中，所述阴极的材质选自不锈钢、镍、钛、镍基合金中的一种。
在本申请的任意实施例中，所述反应容器的材质选自氧化铝。
在本申请的任意实施例中，所述通气管为陶瓷绝缘通气管。
本申请第三方面提供所述的烃类原料转化的方法和/或所述的电化学装置在制备不饱和烃中的用途。
与现有技术相比，本申请的有益效果为：
第一、电解条件：
1、使用电化学的方法在阳极原位生成卤素原子或卤素分子，用于活化稳定的烃类原料分子，将烃类原料高效地转化为卤代烷和卤化氢。
2、使用电化学的方法在阴极原位生成活泼金属和与卤代烷反应，而且可以在阴极原位还原卤化氢，从而实现将烃类原料转化为高价值产物，例如转化为氢气、乙烯、乙炔、丙烯、石墨等。
3、上述反应在所述的电化学体系中即可实现，避免了多个独立步骤和反应器。因此，大大简化了过程。
第二、光照或加热条件：
1、活泼金属可以和卤代烷和卤化氢反应生成氢气、乙烯，乙炔、丙烯、石墨等高价值产物。
2、生成的金属卤化物容易分离，与活泼金属属于不同的相，二者互不混溶，且有密度差。
3、分离出的金属卤化物可以通过电解再生出活泼金属和卤素气体，回收利用，实现一个闭环过程，不仅过程简单有效，而且实现了资源的回收利用。
第三、总体方法：
1、反应条件相对更温和。无需过高压强，在较低压强如1～5个大气压即可实现，比常规方法的20～100个大气压明显降低。反应温度较低，只有约200-600℃，比常规方法的850℃明显降低。
2、反应过程更简单。不必提前分离烃类原料中的含硫气体和二氧化碳，可以直接将原料气体通入到该体系进行转化。
3、避免生成副产物，比如二氧化碳产物，也避免了传统催化剂因表面积碳或者其它惰性物质(包括固态氧化物、固态盐)而中毒失活的现象。
4、性价比高，不使用贵金属，使用的材料来源丰富，价格低廉，成本低。
附图说明
图1显示为本发明的电化学装置的第一种局部结构示意图。
图2显示为本发明的电化学装置的第二种局部结构示意图。
图3显示为本发明的电化学装置的第一种整体结构示意图。
图4显示为本发明的电化学装置的第二种整体结构示意图。
图5显示为本发明的实施例1的输出气体的核磁谱图。
图6显示为本发明的实施例1的输出气体有关氢气的气相色谱图。
图7显示为本发明的实施例1的输出气体有关乙烯的气相色谱图。
图8显示为本发明的实施例1的输出气体有关乙炔的气相色谱图。
图9显示为本发明的实施例2的输出气体的核磁谱图。
图10显示为本发明的实施例3的输出气体的核磁谱图。
图11显示为本发明的实施例4的输出气体的核磁谱图。
图12显示为本发明的实施例5的输出气体的核磁谱图。
图13显示为本发明的实施例6的输出气体的核磁谱图。
图14显示为本发明的实施例7的输出气体的核磁谱图。
图15显示为本发明的实施例8的输出气体的核磁谱图。
图16显示为本发明的实施例9的输出气体有关氢气的气相色谱图。
图17显示为本发明的实施例9的输出气体有关乙烯的气相色谱图。
图18显示为本发明的实施例9的输出气体有关乙炔的气相色谱图。
图19显示为本发明的实施例10的有关三氯甲烷的气相色谱图。
图20显示为本发明的实施例10的在400℃下反应输出气体有关乙烯的气相色谱图。
图21显示为本发明的实施例10的在400℃下反应输出气体有关乙炔的气相色谱图。
图22显示为本发明的实施例10的在500℃下反应输出气体有关乙烯的气相色谱图。
图23显示为本发明的实施例10的在500℃下反应输出气体有关乙炔的气相色谱图。
图24显示为本发明的实施例11的有关二氯甲烷的气相色谱图。
图25显示为本发明的实施例11的在400℃下反应输出气体有关乙烯的气相色谱图。
图26显示为本发明的实施例11的在400℃下反应输出气体有关乙炔的气相色谱图。
图27显示为本发明的实施例11的在500℃下反应输出气体有关乙烯的气相色谱图。
图28显示为本发明的实施例12的在500℃下反应输出气体有关乙烯的气相色谱图。
图29显示为本发明的实施例12的在500℃下反应输出气体有关乙炔的气相色谱图。
图30显示为本发明的实施例1的凝固盐上方银色块状金属的XRD表征结果。
图31显示为本发明的实施例1的凝固盐上方黑色物质的XRD表征结果。
元件标号说明：
1                     反应容器
2                     阴极
3                     阳极
4                     金属卤化物熔融盐单元
5                      通气管
6                      供气口
7                      独立腔室
具体实施方式
为了使本申请的发明目的、技术方案和有益效果更加清晰，下面结合实施例对本申请作进一步说明。应理解，所述实施例只用于解释本申请，并非用于限定申请的范围。下述实施例中所使用的试验方法如无特殊说明，均为常规方法，熟悉此技术的人士可由本说明所揭露的内容容易地了解本申请的其他优点及功效。
本申请所公开的“范围”以下限和上限的形式来限定，给定范围是通过选定一个下限和一个上限进行限定的，选定的下限和上限限定了特别范围的边界。这种方式进行限定的范围可以是包括端值或不包括端值的，并且可以进行任意地组合，即任何下限可以与任何上限组合形成一个范围。例如，如果针对特定参数列出了60～120和80～110的范围，理解为60～110和80～120的范围也是预料到的。此外，如果列出的最小范围值1和2，和如果列出了最大范围值3，4和5，则下面的范围可全部预料到：1～3、1～4、1～5、2～3、2～4和2～5。在本申请中，除非有其他说明，数值范围“a～b”表示a到b之间的任意实数组合的缩略表示，其中a和b都是实数。例如数值范围“0～5”表示本文中已经全部列出了“0～5”之间的全部实数，“0～5”只是这些数值组合的缩略表示。另外，当表述某个参数为≥2的整数，则相当于公开了该参数为例如整数2、3、4、5、6、7、8、9、10、11、12等。
如果没有特别的说明，本申请的所有步骤可以顺序进行，也可以随机进行，优选是顺序进行的。例如，所述方法包括步骤1)和2)，表示所述方法可包括顺序进行的步骤1)和2)，也可以包括顺序进行的步骤2)和1)。
本申请的发明人经过大量探索研究，发现了一种烃类原料高效转化的方法及其电化学装置，在相对较低的温度条件下，有效活化烃类原料气体制备高价值产物，包括氢气、乙烯、乙炔、丙烯等，在此基础上完成了本申请。
本申请第一方面提供一种烃类原料转化的方法，包括以下步骤：
1)将烃类原料气体与卤素物质反应生成卤代烷和卤化氢；
2)将步骤1)提供的卤代烷与活泼金属反应，生成第一不饱和烃和第一金属卤化物；
3)将步骤1)提供的卤化氢与活泼金属反应，生成第二金属卤化物和氢气。
本申请提供的烃类原料转化的方法中，步骤1)是在电解体系、光照、加热条件中的一 种或多种的组合情况下进行。
本申请提供的烃类原料转化的方法中，步骤1)中，所述烃类原料气体选自甲烷、乙烷、丙烷、天然气中的一种或多种的组合。优选地，所述烃类原料气体选自甲烷和/或乙烷。更优选地，所述烃类原料气体选自乙烷。
本申请提供的烃类原料转化的方法中，步骤1)中，所述卤素物质包括卤素离子、卤素原子、卤素分子中的一种或多种的组合。优选地，所述卤素原子选自Cl、Br、I中的一种或多种的组合；所述卤素离子包括第一卤素离子；所述卤素分子包括第一卤素分子和/或第二卤素分子；更优选地，所述第一卤素离子选自Cl -、Br -、I -中的一种或多种的组合；所述第一卤素分子或第二卤素分子选自Cl 2、Br 2、I 2中的一种或多种的组合。其中，卤素原子作为中间态参与反应，中间态为自由基，比较活泼。所述卤代烷包括第一卤代烷和/或第二卤代烷；所述卤化氢包括第一卤化氢和/或第三卤化氢。其中，第一卤代烷或第二卤代烷例如可以是一卤代烷、二卤代烷或多卤代烷。一卤代烷例如可以是一氯代烷、一溴代烷、或一碘代烷等。其他不再一一赘述。第一卤化氢或第三卤化氢选自氯化氢、溴化氢、碘化氢等。
本申请提供的烃类原料转化的方法中，步骤2)或步骤3)中，具体到每种第一金属卤化物，均可以对应由具体选择的卤代烷与具体选择的活泼金属获得。例如，一氯代烷与Na反应获得NaCl。第二金属卤化物的解释同前。
本申请提供的烃类原料转化的方法中，步骤2)或步骤3)中，所述活泼金属包括金属单质和/或液态合金。金属单质包括第一金属单质。优选地，第一金属单质选自碱金属和/或碱土金属。更优选地，第一金属单质选自Li、Na、K、Rb、Cs、Mg、Ca、Sr、Ba中的一种或多种的组合。液态合金是指将金属单质溶于另一种低熔点的金属获得。优选地，低熔点的金属包括Ga、In、Sn、Pb、Zn、Bi、Sb中的一种或多种的组合。所述液态合金中参与反应的是金属单质，所述低熔点的金属的作用是形成合金，从而降低对周围环境的腐蚀性。
本申请提供的烃类原料转化的方法中，步骤3)中，所述氢气包括第一氢气和/或第三氢气。
本申请提供的烃类原料转化的方法中，当步骤1)在电解体系中进行时，所述电解体系包括阳极、阴极和金属卤化物熔融盐。所述阳极的材质选自石墨。所述阴极的材质选自不锈钢、镍、钛、镍基合金中的一种或多种的组合。
本申请提供的烃类原料转化的方法中，当步骤1)在电解体系中进行时，所述金属卤化物熔融盐选自第三金属卤化物的熔融体。所述熔融体是指在当温度达到第三金属卤化物的熔点时，第三金属卤化物会达到熔融状态。所述熔点选自200～600℃；优选为200～300℃、 300～400℃、400～500℃、或500～600℃等。金属卤化物熔融盐在熔融状态下提供第三金属卤化物。在熔融状态下，第三金属卤化物以离子状态存在，第三金属卤化物用于提供第一金属离子和第一卤素离子，作为金属卤化物熔盐电解质。其中，第一金属离子选自碱金属离子和/或碱土金属离子；更优选地，第一金属离子选自Li +、Na +、K +、Rb +、Cs +、Mg 2+、Ca 2+、Sr 2+、Ba 2+中的一种或多种的组合。
本申请提供的烃类原料转化的方法中，当步骤1)在电解体系中进行时，阳极发生如下2种反应的一种或多种：
A1)第一卤素离子在阳极发生氧化反应以提供第一卤素分子，所述烃类原料气体与第一卤素分子在阳极发生氧化反应，以提供第一卤代烷和第一卤化氢。
在具体实施例中，当第一卤素离子为氯离子，烃类原料气体为甲烷时，例如生成的第一卤代烷可以为一氯甲烷，第一卤化氢为氯化氢，具体反应式为2Cl -＝Cl 2(g)+2e -，Cl 2(g)+CH 4(g)＝CH 3Cl(g)+HCl(g)。
A2)第一卤素离子与所述烃类原料在阳极发生氧化反应，以提供第一卤代烷和第一卤化氢。
在具体实施方式中，当第一卤素离子为氯离子，烃类原料气体为甲烷时，例如生成的第一卤代烷可以为一氯甲烷，第一卤化氢为氯化氢，具体反应式则为CH 4(g)+2Cl -＝CH 3Cl(g)+HCl(g)+2e -。
阳极反应生成的第一卤化氢和第一卤代烷大部分以气体形式存在。至少部分的第一卤代烷和至少部分的第一卤化氢可以扩散至阴极发生还原反应。在气体扩散过程中，阳极中还未转化的烃类原料气体还可以和第一卤素离子或第一卤素分子继续反应生成更多的第一卤代烷和第一卤化氢。
本申请提供的烃类原料转化的方法中，当步骤1)在电解体系中进行时，第三金属卤化物选自金属氯化物、金属溴化物、金属碘化物中的一种或多种的组合。更优选地，金属氯化物选自LiCl、NaCl、KCl、RbCl、CsCl、MgCl 2、CaCl 2、SrCl 2、BaCl 2、ZnCl 2中的一种或多种的组合。金属溴化物选自LiBr、NaBr、KBr、RbBr、CsBr、MgBr 2、CaBr 2、SrBr 2、BaBr 2、ZnBr 2中的一种或多种的组合。金属碘化物选自LiI、NaI、KI、RbI、CsI、MgI 2、CaI 2、SrI 2、BaI 2、ZnI 2中的一种或多种的组合。
本申请提供的烃类原料转化的方法中，当步骤1)在电解体系中进行时，对于单位体积1cm 3的金属卤化物熔融盐，通入所述烃类原料气体的流速为0.02～0.8cm 3/min。优选地，对于单位体积(1cm 3)的熔融盐，所述供气口的气体流速为0.072cm 3/min。在本申请的具体实施 例中，对于单位体积(1cm 3)的熔融盐，如果所述供气口的气体流速为0.02～0.8cm 3/min，那么对于70cm 3的熔融盐，气体实际流速为(0.02×70＝1.4)～(0.8×70＝56)cm 3/min。在本申请的优选实施例中，对于单位体积(1cm 3)的熔融盐，如果所述供气口的气体流速为0.072cm 3/min，那么对于70cm 3的熔融盐，气体实际流速为0.072×70＝5.04cm 3/min。限定气体流速是为了使烃类原料气体量与阳极生成的第一卤素分子气体量接近。如果烃类原料气体量远小于阳极生成的第一卤素分子气体量，那么多余的未与烃类原料反应的第一卤素分子气体将上浮至阴极，消耗阴极生成的第一金属单质和第一氢气，从而减少高价值产物的生成量；如果烃类原料气体流速过高，会降低烃类原料气体在反应器中的保留时间，从而降低转化率。
本申请提供的烃类原料转化的方法中，当步骤1)在电解体系中进行时，所述电解质体系的反应温度为200～600℃；优选为200～300℃、300～400℃、400～500℃、或500～600℃等。所述电解质体系的反应电压为3～10V；优选为3～4V、4～5V、5～8V、或8～10V等。
本申请提供的烃类原料转化的方法中，当步骤1)在电解体系中进行时，所述还原反应包括以下3种情况：
B1)所述第三金属卤化物得电子以提供第一金属单质和第二卤素离子；第一金属单质与第一卤代烷反应生成第一不饱和烃和第一金属卤化物。第一不饱和烃例如可以是烯烃或炔烃。烯烃例如可以是乙烯、丙烯等。炔烃例如可以是乙炔、丙炔等。当所述第一卤代烷为CCl 4时，与所述第一金属单质会生成石墨和第一金属卤化物，或CCl 4自身分解成石墨和氯气。所述石墨可以位于第三金属卤化物的底部或者浮于第三金属卤化物的上方或者混于第三金属卤化物的内部，这取决于石墨和第三金属卤化物的密度、第三金属卤化物的黏度、和通气情况等。
在具体实施例中，当第三金属卤化物为NaCl时，反应式为NaCl+e -＝Na+Cl -。当第一金属单质为Na，第一卤代烷为CH 2Cl 2时，反应式为2CH 2Cl 2+4Na＝C 2H 4+4NaCl。当第一金属单质为Na，第一卤代烷为CHCl 3时，反应式为2CHCl 3+6Na＝C 2H 2+6NaCl。当第一金属单质为Na，第一卤代烷为CH 2Cl-CH 2Cl时，反应式为CH 2Cl-CH 2Cl+2Na＝C 2H 4+2NaCl。当第一金属单质为Na，第一卤代烷为CCl 4时，反应式为CCl 4+4Na＝C(石墨)+4NaCl。
B2)所述第三金属卤化物得电子以提供第一金属单质和第二卤素离子；第一金属单质与第一卤化氢反应生成第一氢气和第二金属卤化物。所述第二卤素离子选自Cl -、Br -、I -中的一种或多种的组合。
在具体实施例中，当第三金属卤化物为LiCl时，反应式为LiCl+e -＝Li+Cl -，Li+HCl＝1/2H 2+LiCl。
B3)所述第一卤化氢得电子生成第二氢气和第三卤素离子。所述第三卤素离子选自Cl -、 Br -、I -中的一种或多种的组合。
在具体实施例中，当所述第一卤化氢为HCl，反应式为HCl+e -＝1/2H 2+Cl -。
本申请提供的烃类原料转化的方法中，当步骤1)在电解体系中进行时，还包括对剩余部分的所述第一卤代烷和剩余部分的所述第一卤化氢的后处理步骤，包括以下5种方式的一种或多种组合：
C1)将剩余部分的所述第一卤代烷与碱性物质反应生成醇、醛、羧酸和第四金属卤化物，既可以有效利用第一卤代烷，又可以回收更多卤素元素。优选地，所述碱性物质包括碱水溶液、碱性固体或碱性熔融体中的一种或多种的组合。更优选地，所述碱水溶液选自氢氧化锂水溶液、氢氧化钠水溶液、氢氧化钾水溶液等常规碱性溶液。所述碱性固体选自氢氧化锂、氢氧化钠、氢氧化钾中等常规固体。所述碱性熔融体选自熔融氢氧化锂、熔融氢氧化钠、熔融氢氧化钾等。第四金属卤化物选自金属氯化物、金属溴化物、金属碘化物中的一种或多种的组合。更优选地，金属氯化物选自LiCl、NaCl、KCl、RbCl、CsCl、MgCl 2、CaCl 2、SrCl 2、BaCl 2、ZnCl 2中的一种或多种的组合。金属溴化物选自LiBr、NaBr、KBr、RbBr、CsBr、MgBr 2、CaBr 2、SrBr 2、BaBr 2、ZnBr 2中的一种或多种的组合。金属碘化物选自LiI、NaI、KI、RbI、CsI、MgI 2、CaI 2、SrI 2、BaI 2、ZnI 2中的一种或多种的组合。
C2)将剩余部分的所述第一卤代烷在催化剂的作用下反应生成第二不饱和烃和第二卤化氢。所述催化剂选自沸石催化剂。第二不饱和烃例如可以是烯烃或炔烃。烯烃例如可以是乙烯、丙烯等。炔烃例如可以是乙炔、丙炔等。第二卤化氢选自氯化氢、溴化氢、碘化氢等。
C3)将剩余部分的所述第一卤代烷与所述活泼金属反应生成第三不饱和烃和第五金属卤化物。第三不饱和烃例如可以是烯烃或炔烃。烯烃例如可以是乙烯、丙烯等。炔烃例如可以是乙炔、丙炔等。第五金属卤化物选自金属氯化物、金属溴化物、金属碘化物中的一种或多种的组合。更优选地，金属氯化物选自LiCl、NaCl、KCl、RbCl、CsCl、MgCl 2、CaCl 2、SrCl 2、BaCl 2、ZnCl 2中的一种或多种的组合。金属溴化物选自LiBr、NaBr、KBr、RbBr、CsBr、MgBr 2、CaBr 2、SrBr 2、BaBr 2、ZnBr 2中的一种或多种的组合。金属碘化物选自LiI、NaI、KI、RbI、CsI、MgI 2、CaI 2、SrI 2、BaI 2、ZnI 2中的一种或多种的组合。如本申请的实施例10～12所示。
C4)将剩余部分的所述第一卤代烷回收，再次通入进行反应，生成第一不饱和烃和第一金属卤化物。
C5)将剩余部分的所述第一卤化氢与所述活泼金属反应生成第六金属卤化物和第三氢气。
本申请提供的烃类原料转化的方法中，当步骤1)在光照条件和/或加热条件下进行时， 所述光照条件是波长为200～450nm；优选为200～250nm、250～350nm、或350～450nm等。所述光照条件的反应温度为20～600℃；优选为20～100℃、100～200℃、或200～600℃等。所述加热条件是在250℃以上。在所述光照条件和/或加热条件下，所述烃类原料气体与第二卤素分子气体反应以提供第二卤代烷和第三卤化氢。第二卤代烷与活泼金属反应以提供第三不饱和烃和第五金属卤化物。第三卤化氢与所述活泼金属反应以提供第六金属卤化物和第三氢气。第六金属卤化物选自金属氯化物、金属溴化物、金属碘化物中的一种或多种的组合。更优选地，金属氯化物选自LiCl、NaCl、KCl、RbCl、CsCl、MgCl 2、CaCl 2、SrCl 2、BaCl 2、ZnCl 2中的一种或多种的组合。金属溴化物选自LiBr、NaBr、KBr、RbBr、CsBr、MgBr 2、CaBr 2、SrBr 2、BaBr 2、ZnBr 2中的一种或多种的组合。金属碘化物选自LiI、NaI、KI、RbI、CsI、MgI 2、CaI 2、SrI 2、BaI 2、ZnI 2中的一种或多种的组合。
在本申请的任意实施例中，当步骤1)在光照条件和/或加热条件下进行时，还包括后处理步骤：将第五金属卤化物和/或第六金属卤化物电解以提供第二金属单质和第二卤素分子气体，并回收第二金属单质用于步骤2)或步骤3)中，回收第二卤素分子气体用于步骤1)中。第二金属单质选自Li、Na、K、Rb、Cs、Mg、Ca、Sr、Ba中的一种或多种的组合。
本申请另一方面提供一种电化学装置，包括反应容器1，所述反应容器1中包括金属卤化物熔融盐单元4。所述金属卤化物熔融盐单元4中设有阳极3和阴极2。还包括用于给阳极3供气的通气管5。所述通气管5与金属卤化物熔融盐单元4连通。所述通气管5上设有供气口6。所述供气口6的气体选自烃类原料气体。所述烃类原料气体选自甲烷、乙烷、丙烷、天然气中的一种或多种的组合。优选地，所述烃类原料气体选自甲烷和/或乙烷。更优选地，所述烃类原料气体选自乙烷。
本申请提供的电化学装置中，所述金属卤化物熔融盐单元4的材质选自金属卤化物熔融盐。所述金属卤化物熔融盐选自第三金属卤化物的熔融体。所述第三金属卤化物选自LiCl、NaCl、KCl、RbCl、CsCl、MgCl 2、CaCl 2、SrCl 2、BaCl 2、ZnCl 2、LiBr、NaBr、KBr、RbBr、CsBr、MgBr 2、CaBr 2、SrBr 2、BaBr 2、ZnBr 2、LiI、NaI、KI、RbI、CsI、MgI 2、CaI 2、SrI 2、BaI 2、ZnI 2的一种或多种。
本申请提供的电化学装置中，所述阳极3的材质选自石墨。所述阴极2的材质选自不锈钢、镍、钛、镍基合金中的一种。所述反应容器1的材质选自氧化铝。所述反应容器1的高度为30～60cm。所述通气管5为陶瓷绝缘通气管。
本申请提供的电化学装置中，所述阳极3比通气管5更靠近所述反应容器1的底部，是为了保证所述阳极3伸出所述通气管5，从而能够与所述金属卤化物熔融盐单元4接触。所 述阳极3浸入所述金属卤化物熔融盐单元4的长度为10～15cm。所述通气管5浸入所述金属卤化物熔融盐单元4的长度为7～12cm。所述阴极2浸入所述金属卤化物熔融盐单元4的长度为4～9cm。
本申请提供的电化学装置中，所述通气管5套设于所述阳极3。如图1所示，所述阴极2例如可以套设于所述通气管5外，在此情况中，所述通气管5比所述阴极2更靠近所述反应容器1的底部，便于所述通气管5可以与所述金属卤化物熔融盐单元4接触，如此可以形成在所述金属卤化物熔融盐单元4中，从长到短：阳极3>通气管5>阴极2。如图2所示，所述阴极2也可以与所述通气管5分离，单独设于所述金属卤化物熔融盐单元4中，在此种情况下，所述阳极3例如可以比所述阴极2更靠近所述反应容器1的底部，也可以跟所述阴极2齐平，或者可以比所述阴极2更远离所述反应容器1的底部。
本申请提供的电化学装置中，还包括独立腔室7。所述独立腔室7与所述反应容器1相连，且不与所述金属卤化物熔融盐单元4接触。所述独立腔室7中设有活泼金属。所述活泼金属包括金属单质和/或液态合金。所述金属单质包括Li、Na、K、Rb、Cs、Mg、Ca、Sr、Ba中的一种或多种的组合。所述液态合金是指所述金属单质熔于另一种低熔点金属，所述低熔点金属包括Ga、In、Sn、Pb、Zn、Bi、Sb中的一种或多种的组合。所述低熔点金属不发生反应，其作用为形成液态合金，所述液态合金对所述独立腔室7的腐蚀性比较低。如图3所示，所述独立腔室7设于所述反应容器1内部，例如可以设于顶部。如图4所示，所述独立腔室7设于所述反应容器外部。
本申请提供的电化学装置中，在外加电压和温度条件下运行。所述电压为3～10V；优选为3～4V、4～5V、5～8V、或8～10V等。所述温度为200～600℃；优选为200～300℃、300～400℃、400～500℃、或500～600℃等。
本申请提供的电化学装置中，在供气口6通入烃类原料气体，在所述阳极3发生氧化反应，烃类原料气体与所述金属卤化物熔融盐单元4提供的卤素离子反应，生成第一卤代烷和第一卤化氢。
本申请提供的电化学装置中，至少部分的所述第一卤代烷和至少部分的所述第一卤化氢扩散至所述阴极2，发生还原反应提供第一氢气、第二卤素离子、第一不饱和烃和第二金属卤代物中的一种或多种的组合。
图3和图4中，阳极3产生的剩余部分的所述第一卤代烷和剩余部分的所述第一卤化氢上浮至所述独立腔室7中，并与所述活性金属反应生成第三不饱和烃、第五金属卤化物、第六金属卤化物和第三氢气。具体的，当剩余部分的所述第一卤代烃和活性金属反应时，生成 第三不饱和烃和第五金属卤化物。具体的，当剩余部分的所述第一卤化氢和活泼金属反应时，生成第六金属卤化物和第三氢气。
图3和图4中，所述烃类原料气体也可以与第二卤素分子气体在独立腔室中反应，生成第二卤代烷和第三卤化氢。第二卤代烷可以与活泼金属反应，生成第三不饱和烃和第五金属卤化物。第三卤化氢可以与活泼金属反应，生成第六金属卤化物和第三氢气。
图3和图4中，可以从上述两种途径生成第三不饱和烃，从而进一步增加总不饱和烃的生成量。同时，生成的第五金属卤化物和第六金属卤化物可以浮到液态合金表面，不会混溶，易于分离出金属卤化物，并重新用作电化学反应的金属卤化物熔盐单元4。
本申请另一方面提供所述的烃类原料转化的方法和/或所述的电化学装置在制备不饱和烃中的用途。不饱和烃可作为化工原料，具有很高的工业价值。
下面通过实施例对本申请予以进一步说明，但并不因此而限制本申请的范围。
下述是实施例的甲烷转化率和乙烷转化率的计算公式：甲烷转化率(％)＝(通入反应器的甲烷量-流出的甲烷量)/(通入反应器的甲烷量)*100％；乙烷转化率(％)＝(通入反应器的乙烷量-流出的乙烷量)/(通入反应器的乙烷量)*100％。
实施例1
使用LiCl-NaCl-KCl熔盐电解质的电化学装置转化甲烷制备高价值产物
称取65.27g 44％LiCl-25％NaCl-31％KCl(摩尔分数)，装入内径为22mm的一端封头的氧化铝反应容器中。将氧化铝反应容器置于高温管式炉中。在500℃的温度条件下，盐熔化形成熔盐，高度约为10cm。如图1所示，将石墨阳极(直径：3mm)插到熔盐电解质底部，石墨阳极的外面包围着陶瓷绝缘通气管，材质为氧化铝。石墨阳极伸出陶瓷绝缘通气管约3cm。阴极是一根不锈钢管，插入盐电解质约4cm。不锈钢管阴极套在陶瓷绝缘通气管的外面。
将甲烷和氮气的混合气通过陶瓷绝缘通气管通到阳极表面。甲烷作为烃类原料，流速为3cm 3/min；氮气作为载气，流速为17cm 3/min。施加6V的电压，使用氘代氯仿(CDCl 3)溶剂收集反应器输出气体，并使用核磁分析，如图5所示，发现了明显的一氯甲烷和二氯甲烷的信号，证明了甲烷在阳极的有效活化。使用气相色谱仪(GC)分析排出气体的成分，发现在电解的第5个小时，甲烷的转化率达到了60％，氢气、乙烯和乙炔的输出量分别为3cm 3/min、0.035cm 3/min和0.14cm 3/min。氢气、乙烯和乙炔的GC信号分别如图6，图7和图8所示。以上结果显示，在含有LiCl-NaCl-KCl熔盐电解质的电化学体系中，在500℃和施加6V电压的条件下，甲烷有效地活化，氢气、乙烯和乙炔的产率较高。实验结束后，打开反应器，常 温下金属氯化物熔融电解质会变成凝固盐，在凝固盐的上方发现了银色块状金属，取样并使用XRD表征，结果如图30所示，表明该样品的主相是金属钠，这说明在电解过程中在阴极生成了金属钠。此外，在凝固盐的上方发现黑色物质，用拉曼光谱仪表征，结果如图31所示，在拉曼位移为1360cm -1和1590cm -1处发现了石墨的特征峰，这说明在反应过程中，有一部分甲烷可以转化为四氯甲烷，然后生成了高价值的石墨。
实施例2
使用LiCl-NaCl-KCl熔盐电解质的电化学装置转化甲烷制备高价值产物
称取97.91g 44％LiCl-25％NaCl-31％KCl(摩尔分数)，装入内径为22mm的一端封头的氧化铝反应容器中。将氧化铝反应容器置于高温管式炉中。在300℃的温度条件下保温并且抽真空12个小时除去盐中的水分。升温至600℃，盐熔化形成熔盐，高度约为15cm。如图1所示，将石墨阳极(直径：3mm)插到熔盐电解质底部，石墨阳极的外面包围着陶瓷绝缘通气管，材质为氧化铝。石墨阳极伸出陶瓷绝缘通气管约3cm。阴极是一根不锈钢管，插入盐电解质约9cm。不锈钢管阴极套在陶瓷绝缘通气管的外面。
将甲烷和氮气的混合气通过陶瓷绝缘通气管通到阳极表面。甲烷作为烃类原料，流速为3cm 3/min；氩气作为载气，流速为17cm 3/min。施加0.75A的恒定电流，使用DMSO溶剂收集输出气体并使用核磁分析，如图9所示，出现了一氯甲烷、二氯甲烷和三氯甲烷的信号，证明了甲烷在阳极的有效活化。使用气相色谱仪分析排出气体的成分，发现在电解的第4.5个小时，甲烷的转化率达到了40％，氢气、乙烯和乙炔的输出量分别为2.5cm 3/min、0.05cm 3/min和0.07cm 3/min。以上结果显示，在含有LiCl-NaCl-KCl熔盐电解质的电化学体系中，在600℃和施加0.75A的恒定电流条件下，甲烷有效地活化，氢气、乙烯和乙炔的产率较高。反应结束后，打开反应器，常温下金属氯化物熔融电解质会变成凝固盐，在凝固盐的上方发现了石墨。
实施例3
称取65.27g 44％LiCl-25％NaCl-31％KCl(摩尔分数)，装入内径为22mm的一端封头的氧化铝反应容器中。将氧化铝反应容器置于高温管式炉中。在300℃的温度条件下保温并且抽真空12个小时除去盐中的水分。升温至500℃，盐熔化形成熔盐，高度约为10cm。如图1所示，将石墨阳极(直径：3mm)插到熔盐电解质底部，石墨阳极的外面包围着陶瓷绝缘通气管，材质为氧化铝。石墨阳极伸出陶瓷绝缘通气管约3cm。阴极是一根不锈钢管，插入 盐电解质约4cm。不锈钢管阴极套在陶瓷绝缘通气管的外面。
将甲烷和氮气的混合气通过陶瓷绝缘通气管通到阳极表面。甲烷作为烃类原料，流速为3cm 3/min；氩气作为载气，流速为17cm 3/min。施加0.75A的恒定电流，使用DMSO溶剂收集输出气体并使用核磁分析，如图10所示，出现了一氯甲烷、二氯甲烷和三氯甲烷的信号，证明了甲烷在阳极的有效活化。反应结束后，打开反应器，常温下金属氯化物熔融电解质会变成凝固盐，在凝固盐的上方发现了石墨。
实施例4
使用LiCl-KCl熔盐电解质的电化学装置转化甲烷制备高价值产物的方法
称取63.43g 60％LiCl-40％KCl(摩尔分数)，装入内径为22mm的一端封头的氧化铝反应容器中。将氧化铝反应容器置于高温管式炉中。在450℃的温度条件下，盐熔化形成熔盐，高度约为10cm。如图1所示，将石墨阳极(直径：3mm)插到熔盐电解质底部，石墨阳极的外面包围着陶瓷绝缘通气管，材质为氧化铝。石墨阳极伸出陶瓷绝缘通气管约3cm。阴极是一根不锈钢管，插入盐电解质约4cm。不锈钢管阴极套在陶瓷绝缘通气管的外面。
将甲烷和氮气的混合气通过陶瓷绝缘通气管通到阳极表面。甲烷作为烃类原料，流速为3cm 3/min；氮气作为载气，流速为17cm3/min。施加6V的电压，使用氘代氯仿溶剂收集输出气体并使用核磁分析，如图11所示，发现了明显的二氯甲烷的信号，证明了甲烷在阳极的有效活化。使用气相色谱仪分析排出气体的成分，发现在电解的第3小时40分，甲烷的转化率达到了50％，氢气的产率约为1cm 3/min，有少量的乙烯和乙炔生成。以上结果显示，在含有LiCl-KCl熔盐电解质的电化学体系中，在450℃和施加6V电压的条件下，甲烷有效地活化，生成了氢气、乙烯和乙炔。
实施例5
称取63.43g 60％LiCl-40％KCl(摩尔分数)，装入内径为22mm的一端封头的氧化铝反应容器中。将氧化铝反应容器置于高温管式炉中。在300℃的温度条件下保温并且抽真空12个小时除去盐中的水分。升温至500℃，盐熔化形成熔盐，高度约为10cm。如图1所示，将石墨阳极(直径：3mm)插到熔盐电解质底部，石墨阳极的外面包围着陶瓷绝缘通气管，材质为氧化铝。石墨阳极伸出陶瓷绝缘通气管约3cm。阴极是一根不锈钢管，插入盐电解质约4cm。不锈钢管阴极套在陶瓷绝缘通气管的外面。
将甲烷和氮气的混合气通过陶瓷绝缘通气管通到阳极表面。甲烷作为烃类原料，流速为3cm 3/min；氮气作为载气，流速为17cm 3/min。施加6V的电压，使用氘代氯仿溶剂收集输出 气体并使用核磁分析，如图12所示，发现二氯甲烷的信号相比于450℃更强了，证明了甲烷在阳极的有效活化，升高温度有利于二氯甲烷的生成。使用气相色谱仪分析排出气体的成分，甲烷转化率大致在80％且比较稳定，氢气产量大致在1ml/min。乙烯和乙炔的产量明显上升，乙炔最高可达到0.012ml/min，乙烯最高有0.002ml/min。
实施例6
使用LiCl-KCl-MgCl 2熔盐电解质的电化学装置转化甲烷制备高价值产物
称取70.18g 48％LiCl-32％KCl-20％MgCl 2(摩尔分数)，装入内径为22mm的一端封头的氧化铝反应容器中。将氧化铝反应容器置于高温管式炉中。在300℃的温度条件下保温并且抽真空12个小时除去盐中的水分。升温至500℃，盐熔化形成熔盐，高度约为10cm。如图1所示，将石墨阳极(直径：3mm)插到熔盐电解质底部，石墨阳极的外面包围着陶瓷绝缘通气管，材质为氧化铝。石墨阳极伸出陶瓷绝缘通气管约3cm。阴极是一根不锈钢管，插入盐电解质约4cm。不锈钢管阴极套在陶瓷绝缘通气管的外面。
将甲烷和氮气的混合气通过陶瓷绝缘通气管通到阳极表面。甲烷作为烃类原料，流速为3cm 3/min；氩气作为载气，流速为17cm 3/min。施加1A的恒定电流，使用DMSO溶剂收集输出气体并使用核磁分析，如图13所示，出现了一氯甲烷的信号，证明了甲烷在阳极的有效活化。
实施例7
使用LiCl-KCl-MgCl 2熔盐电解质的电化学装置转化甲烷制备高价值产物
称取70.18g 48％LiCl-32％KCl-20％MgCl 2(摩尔分数)，装入内径为22mm的一端封头的氧化铝反应容器中。将氧化铝反应容器置于高温管式炉中。在300℃的温度条件下保温并且抽真空12个小时除去盐中的水分。升温至550℃，盐熔化形成熔盐，高度约为10cm。如图1所示，将石墨阳极(直径：3mm)插到熔盐电解质底部，石墨阳极的外面包围着陶瓷绝缘通气管，材质为氧化铝。石墨阳极伸出陶瓷绝缘通气管约3cm。阴极是一根不锈钢管，插入盐电解质约4cm。不锈钢管阴极套在陶瓷绝缘通气管的外面。
将甲烷和氮气的混合气通过陶瓷绝缘通气管通到阳极表面。甲烷作为烃类原料，流速为3cm 3/min；氩气作为载气，流速为17cm 3/min。施加1A的恒定电流，使用氘代氯仿溶剂收集输出气体并使用核磁分析，如图14所示，出现了一氯甲烷和二氯甲烷的特征信号，说明升高温度有利于二氯甲烷的形成。
实施例8
使用LiBr-NaBr-KBr熔盐电解质的电化学装置转化甲烷制备高价值产物
称取134.64g 45％LiBr-25％NaBr-30％KBr(摩尔分数)，装入内径为22mm的一端封头的氧化铝反应容器中。将氧化铝反应容器置于高温管式炉中。在300℃的温度条件下保温并且抽真空12个小时除去盐中的水分。升温至500℃，盐熔化形成熔盐，高度约为10cm。如图1所示，将石墨阳极(直径：3mm)插到熔盐电解质底部，石墨阳极的外面包围着陶瓷绝缘通气管，材质为氧化铝。石墨阳极伸出陶瓷绝缘通气管约3cm。阴极是一根不锈钢管，插入盐电解质约4cm。不锈钢管阴极套在陶瓷绝缘通气管的外面。
将甲烷和氮气的混合气通过陶瓷绝缘通气管通到阳极表面。甲烷作为烃类原料，流速为3cm 3/min；氩气作为载气，流速为17cm 3/min。施加1A的恒定电流，使用DMSO做溶剂，收集输出气体并使用核磁分析，如图15所示，出现了二溴甲烷的特征信号，证明了甲烷在阳极的有效活化。使用气相色谱仪分析排出气体的成分，发现在电解的第5小时，甲烷的转化率达到了约55％，H 2的生产速率为0.32cm 3/min。以上结果显示，在含有LiBr-NaBr-KBr熔盐电解质的电化学体系中，在500℃和施加1A电流的条件下，甲烷有效地活化，生成了氢气。
实施例9
使用LiCl-NaCl-KCl熔盐电解质的电化学装置转化乙烷制备高价值产物
称取65.27g 44％LiCl-25％NaCl-31％KCl(摩尔分数)，装入内径为22mm的一端封头的氧化铝反应容器中。将氧化铝反应容器置于高温管式炉中。在300℃的温度条件下保温并且抽真空12个小时除去盐中的水分。升温至500℃，盐熔化形成熔盐，高度约为10cm。如图1所示，将石墨阳极(直径：3mm)插到熔盐电解质底部，石墨阳极的外面包围着陶瓷绝缘通气管，材质为氧化铝。石墨阳极伸出陶瓷绝缘通气管约3cm。阴极是一根不锈钢管，插入盐电解质约4cm。不锈钢管阴极套在陶瓷绝缘通气管的外面。
将乙烷和氩气的混合气通过陶瓷绝缘通气管通到阳极表面。乙烷作为烃类原料，流速为3cm 3/min；氩气作为载气，流速为17cm 3/min。施加1A的恒定电流，使用高精度气相色谱仪分析排出气体的成分。在电解过程中，乙烷的转化率一直是接近100％，氢气和乙烯的产量随电解时间逐渐升高。在电解的第8个小时，氢气生产速率约为3cm 3/min，乙烯生产速率约为1cm 3/min，乙烯的选择性达到25％，乙炔生产速率约为0.25cm 3/min。电解的第7.5小时的气体产物中氢气、乙烯和乙炔的高精度GC信号分别如图16，图17和图18所示。以上结果显示，在含有LiCl-NaCl-KCl熔盐电解质的电化学体系中，在500℃和施加1A电流的条件下， 乙烷接近100％活化，生成了较多的氢气、乙烯和乙炔。
实施例10
钠金属在400℃或500℃温度下和三氯甲烷的反应
实验首先将氩气(流速为17cm 3/min)通过装有5cm高的液态三氯甲烷的洗气瓶后，然后再将气体通入专门分析氯烷的气相色谱仪，并使用甲烷(流速为3cm 3/min)作为标准气体。气相色谱结果给出了明显的三氯甲烷信号，如图19所示。这个结果说明，可以使用氩气通过洗气瓶携带出一定量的三氯甲烷。
称取1g金属钠放置在氧化铝瓷舟中，然后一同转移到内径42mm的石英管内，在氩气(流速为17cm 3/min)中程序升温至400℃或500℃，之后将氩气气流(流速保持为17cm 3/min)流经装有5cm高的液态三氯甲烷的洗气瓶，在室温下携带出一定量的三氯甲烷并且流入反应体系内，在高温下与钠金属发生反应，然后将反应后的气体通入高精度气相色谱仪中表征其成分。根据高精度色相色谱分析结果，金属钠和三氯甲烷在400℃下反应后的气体中含有乙烯和乙炔，分别如图20和图21所示。根据高精度色相色谱分析结果，三氯甲烷和金属钠在500℃下反应的气体中也含有乙烯和乙炔，分别如图22和图23所示。该实施例间接验证了电化学实验中阴极反应生成的钠金属可以和在阳极生成的三氯甲烷反应生成乙烯和乙炔。此外，该实施例也说明了对于电化学体系的阳极中产生的三氯甲烷，如果未完全反应，可以与活泼金属(例如钠)反应生成不饱和烃。
实施例11
钠金属在400℃或500℃温度下和二氯甲烷的反应
实验首先将氩气(流速为17cm 3/min)通过装有5cm高的液态二氯甲烷的洗气瓶后，然后再将气体通入专门分析氯烷的气相色谱仪，并使用甲烷(流速为3cm 3/min)作为标准气体。气相色谱结果给出了明显的二氯甲烷信号，如图24所示。这个结果说明，可以使用氩气通过洗气瓶携带出一定量的二氯甲烷。
称取1g金属钠放置在氧化铝瓷舟中，然后一同转移到内径42mm的石英管内，在氩气(流速为17cm 3/min)中程序升温至400℃或500℃，之后将氩气气流(流速保持为17cm 3/min)流经装有5cm高的液态二氯甲烷的洗气瓶，在室温下携带出一定量的二氯甲烷并且流入反应体系内，在高温下与钠金属发生反应，然后将反应后的气体通入高精度气相色谱仪中表征其成分。根据高精度色相色谱分析结果，金属钠和二氯甲烷在400℃下反应后的气体中含有乙烯和乙炔，分别如图25和图26所示。根据高精度色相色谱分析结果，二氯甲烷和金属钠在 500℃下反应的气体产物主要是乙烯。图27是有关乙烯的气相色谱图。该实施例间接验证了电化学实验中阴极反应生成的钠金属可以和在阳极生成的二氯甲烷反应生成乙烯。此外，该实施例也说明了对于电化学体系的阳极中产生的二氯甲烷，如果未完全反应，可以与活泼金属(例如钠)反应生成不饱和烃。
实施例12
二氯甲烷和Li-Sn合金的反应
称取21.29克60％Li-40％Sn(摩尔分数)合金，放入内径13mm的氧化铝反应器中，在氩气(流速为17cm 3/min)气流中程序升温至500℃，Li-Sn合金融化，高度为5cm。之后将氩气气流(流速保持为17cm 3/min)流经装有10cm高的液态二氯甲烷的洗气瓶，在室温下携带出一定量的二氯甲烷并且流入反应体系内，在高温下与Li-Sn合金发生反应。然后，将反应后的气体通入高精度气相色谱仪中表征其成分。根据高精度色相色谱分析结果，液态Li-Sn合金和二氯甲烷在500℃下反应后的气体中含有乙烯和乙炔，分别如图28和图29所示。
上述实施例仅例示性说明本发明的原理及其功效，而非用于限制本申请。任何熟悉此技术的人士皆可在不违背本申请的精神及范畴下，对上述实施例进行修饰或改变。因此，举凡所属技术领域中具有通常知识者在未脱离本发明所揭示的精神与技术思想下所完成的一切等效修饰或改变，仍应由本申请的权利要求所涵盖。

Claims (11)

  1. 一种烃类原料转化的方法，包括以下步骤：
    1)将烃类原料气体与卤素物质反应生成卤代烷和卤化氢；
    2)将步骤1)提供的卤代烷与活泼金属反应，生成第一不饱和烃和第一金属卤化物；
    3)将步骤1)提供的卤化氢与活泼金属反应，生成第二金属卤化物和氢气。
  2. 如权利要求1所述的烃类原料转化的方法，其特征在于，包括如下条件的任一项或多项：
    a1)步骤1)是在电解体系、光照、加热条件中的一种或多种的组合情况下进行；
    a2)步骤1)中，所述烃类原料气体选自甲烷、乙烷、丙烷、天然气中的一种或多种的组合；优选地，所述烃类原料气体选自甲烷和/或乙烷；更优选地，所述烃类原料气体选自乙烷；
    a3)步骤1)中，所述卤素物质包括卤素离子、卤素原子、卤素分子中的一种或多种的组合；优选地，所述卤素原子选自Cl、Br、I中的一种或多种的组合；所述卤素离子包括第一卤素离子；所述卤素分子包括第一卤素分子和/或第二卤素分子；更优选地，所述第一卤素离子选自Cl -、Br -、I -中的一种或多种的组合；所述第一卤素分子或第二卤素分子选自Cl 2、Br 2、I 2中的一种或多种的组合；
    a4)步骤1)中，所述卤代烷包括第一卤代烷和/或第二卤代烷；所述卤化氢包括第一卤化氢和/或第三卤化氢；
    a5)步骤2)或步骤3)中，所述活泼金属包括金属单质和/或液态合金；液态合金是指将金属单质溶于另一种低熔点的金属获得；优选地，低熔点的金属选自Ga、In、Sn、Pb、Zn、Bi、Sb中的一种或多种的组合；金属单质包括第一金属单质；优选地，所述第一金属单质选自碱金属和/或碱土金属；更优选地，所述第一金属单质选自Li、Na、K、Rb、Cs、Mg、Ca、Sr、Ba中的一种或多种的组合；
    a6)步骤3)中，所述氢气包括第一氢气和/或第三氢气。
  3. 如权利要求2所述的烃类原料转化的方法，其特征在于，当步骤1)在电解体系中进行时，所述电解体系包括阳极、阴极和金属卤化物熔融盐；金属卤化物熔融盐在熔融状态下提供第三金属卤化物，第三金属卤化物用于提供第一金属离子和第一卤素离子，第一金属离子在阴极发生还原反应以提供第一金属单质；
    第一卤素离子在阳极发生氧化反应以提供第一卤素分子，所述烃类原料气体与第一卤素分子在阳极发生氧化反应，以提供第一卤代烷和第一卤化氢；
    和/或，第一卤素离子与所述烃类原料气体在阳极发生氧化反应，以提供第一卤代烷和第一卤化氢；
    优选地，至少部分的所述第一卤代烷和至少部分的所述第一卤化氢扩散到阴极发生还原反应生成第一氢气、第二卤素离子、第一不饱和烃和第二金属卤化物中的一种或多种的组合。
  4. 如权利要求3所述的烃类原料转化的方法，其特征在于，还包括如下条件的任一项或多项：
    c1)所述金属卤化物熔融盐选自第三金属卤化物的熔融体；优选地，所述第三金属卤化物选自金属氯化物、金属溴化物、金属碘化物中的一种或多种的组合；更优选地，所述金属氯化物选自LiCl、NaCl、KCl、RbCl、CsCl、MgCl 2、CaCl 2、SrCl 2、BaCl 2、ZnCl 2中的一种或多种的组合；所述金属溴化物选自LiBr、NaBr、KBr、RbBr、CsBr、MgBr 2、CaBr 2、SrBr 2、BaBr 2、ZnBr 2中的一种或多种的组合；所述金属碘化物选自LiI、NaI、KI、RbI、CsI、MgI 2、CaI 2、SrI 2、BaI 2、ZnI 2中的一种或多种的组合；
    c2)对于单位体积1cm 3的金属卤化物熔融盐，通入所述烃类原料气体的流速为0.02～0.8cm 3/min；
    c3)所述电解质体系的反应温度为200～600℃；所述电解质体系的反应电压为3～10V；
  5. 如权利要求3所述的烃类原料转化的方法，其特征在于，所述还原反应包括以下3种情况任一种或多种的组合：
    d1)所述第三金属卤化物得电子以提供第一金属单质和第二卤素离子；所述第一金属单质与所述第一卤代烷反应生成第一不饱和烃和第一金属卤化物；
    d2)所述第三金属卤化物得电子以提供第一金属单质和第二卤素离子；所述第一金属单质与所述的第一卤化氢反应生成第一氢气和第二金属卤化物；
    d3)所述第一卤化氢得电子生成第二氢气和第三卤素离子。
  6. 如权利要求3所述的烃类原料转化方法，其特征在于，特征d1)中，当所述第一卤代烷为CCl 4时，与所述第一金属单质会反应生成石墨和第一金属卤化物；
    和/或，特征d1)中，当所述第一卤代烷为CCl 4时，自身分解成石墨和氯气。
  7. 如权利要求3所述的烃类原料转化的方法，其特征在于，还包括对剩余部分的所述第一卤代烷和剩余部分的所述第一卤化氢的后处理步骤，包括以下5种方式的一种或多种的组合：
    e1)将剩余部分的所述第一卤代烷与碱性物质反应生成醇、醛、羧酸和第四金属卤化物；优选地，所述碱性物质包括碱水溶液、碱性固体或碱性熔融体中的一种或多种的组合；更优选地，碱水溶液选自氢氧化锂水溶液、氢氧化钠水溶液、氢氧化钾水溶液中的一种或多种的组合；碱性固体选自氢氧化锂、氢氧化钠、氢氧化钾中的一种或多种的组合；碱性熔融体选自熔融氢氧化锂、熔融氢氧化钠、熔融氢氧化钾中的一种或多种的组合；
    e2)将剩余部分的所述第一卤代烷在催化剂的作用下反应生成第二不饱和烃和第二卤化氢；所述催化剂选自沸石催化剂；
    e3)将剩余部分的所述第一卤代烷与所述活泼金属反应生成第三不饱和烃和第五金属卤化物；
    e4)将剩余部分的所述第一卤代烷回收，再次通入进行反应，生成第一不饱和烃和第一金属卤化物；
    e5)将剩余部分的所述第一卤化氢与所述活泼金属反应生成第六金属卤化物和第三氢气。
  8. 如权利要求2所述的烃类原料转化的方法，其特征在于，当步骤1)在光照条件和/或加热条件下进行时：
    所述光照条件是波长为200～450nm，反应温度为20～600℃；所述加热条件是在250℃以上；在所述光照条件和/或加热条件下，所述烃类原料气体与第二卤素分子反应以提供第二卤代烷和第三卤化氢，第二卤代烷与所述活泼金属反应以提供第三不饱和烃和第五金属卤化物，第三卤化氢与所述活泼金属反应以提供第六金属卤化物和第三氢气；
    优选地，还包括后处理步骤：将第五金属卤化物和/或第六金属卤化物电解以提供第二金属单质和第二卤素分子，并回收第二金属单质用于步骤2)或步骤3)中，回收第二卤素分子用于步骤1)中。
  9. 一种电化学装置，其特征在于，包括反应容器(1)，所述反应容器(1)中包括金属卤化物熔融盐单元(4)；所述金属卤化物熔融盐单元(4)中设有阳极(3)和阴极(2)；还包括用于给阳极(3)供气的通气管(5)；所述通气管(5)与金属卤化物熔融盐单元(4)连通。
  10. 如权利要求9所述的电化学装置，其特征在于，还包括如下条件的任一项或多项：
    f1)所述通气管(5)上设有供气口(6)；
    f2)还包括独立腔室(7)；所述独立腔室(7)与所述反应容器(1)相连，且不与所述金属卤化物熔融盐单元(4)接触；
    f3)所述通气管(5)套设于所述阳极(3)；所述阴极(2)套设于所述通气管(5)；
    f4)所述阴极(2)单独设于所述金属卤化物熔融盐(4)中；
    f5)所述阳极(3)比通气管(5)更靠近所述反应容器(1)的底部；
    f6)所述阳极(3)的材质选自石墨；
    f7)所述阴极(2)的材质选自不锈钢、镍、钛、镍基合金中的一种；
    f8)所述反应容器(1)的材质选自氧化铝；
    f9)所述通气管(5)为陶瓷绝缘通气管。
  11. 如权利要求1～8任一项所述的烃类原料转化的方法和/或如权利要求9～10任一项所述的电化学装置在制备不饱和烃中的用途。
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