WO2022116618A1 - 核壳结构的加氢脱氯催化剂、其制备方法及其在三氟氯乙烯连续制备中的应用 - Google Patents

核壳结构的加氢脱氯催化剂、其制备方法及其在三氟氯乙烯连续制备中的应用 Download PDF

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WO2022116618A1
WO2022116618A1 PCT/CN2021/117089 CN2021117089W WO2022116618A1 WO 2022116618 A1 WO2022116618 A1 WO 2022116618A1 CN 2021117089 W CN2021117089 W CN 2021117089W WO 2022116618 A1 WO2022116618 A1 WO 2022116618A1
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active metal
metal
hydrodechlorination
carrier
catalyst
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PCT/CN2021/117089
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English (en)
French (fr)
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刘武灿
李玲
卢春山
石能富
马超峰
李小年
金佳敏
聂娟娟
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中化蓝天集团有限公司
浙江蓝天环保高科技股份有限公司
浙江省化工研究院有限公司
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Priority claimed from CN202011408886.5A external-priority patent/CN112657507B/zh
Priority claimed from CN202011412380.1A external-priority patent/CN112657508B/zh
Priority claimed from CN202011412349.8A external-priority patent/CN112657525B/zh
Application filed by 中化蓝天集团有限公司, 浙江蓝天环保高科技股份有限公司, 浙江省化工研究院有限公司 filed Critical 中化蓝天集团有限公司
Publication of WO2022116618A1 publication Critical patent/WO2022116618A1/zh

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
    • B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/56—Platinum group metals
    • B01J23/60—Platinum group metals with zinc, cadmium or mercury
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/80—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with zinc, cadmium or mercury
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/89—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals
    • 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
    • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
    • B01J27/24—Nitrogen compounds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C17/00—Preparation of halogenated hydrocarbons
    • C07C17/23—Preparation of halogenated hydrocarbons by dehalogenation
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C21/00—Acyclic unsaturated compounds containing halogen atoms
    • C07C21/02—Acyclic unsaturated compounds containing halogen atoms containing carbon-to-carbon double bonds
    • C07C21/18—Acyclic unsaturated compounds containing halogen atoms containing carbon-to-carbon double bonds containing fluorine

Definitions

  • the invention relates to the field of catalysts, in particular to three kinds of core-shell structure hydrodechlorination catalysts with different carriers and different preparation processes, and the application of the core-shell structure hydrodechlorination catalyst in gas-phase hydrodechlorination reaction, Especially in the application of trifluorotrichloroethane in the preparation of trifluorochloroethylene.
  • the catalytic hydrodechlorination technology which replaces the traditional chemical reduction method, has attracted widespread attention in the important monomer reactions for the synthesis of hydrofluorocarbons and other fluorine-containing materials, and is considered to be one of the most economical, green and most promising methods at present. one.
  • common hydrodechlorination catalysts mainly use palladium as the main active component, and magnesium, cobalt, copper, bismuth, etc. as auxiliary agents. Hydrodechlorination performance.
  • European patent EP0053657B1 discloses that platinum group metals are supported on basic magnesium fluoride (such as sodium magnesium fluoride, potassium magnesium fluoride) to prepare a hydrodechlorination catalyst, which can be used for CFC-113 to prepare chlorotrifluoroethylene , the highest conversion rate of CFC-113 is 84%, and the product selectivity is 82-84%.
  • basic magnesium fluoride such as sodium magnesium fluoride, potassium magnesium fluoride
  • European patent EP0747337B1 and Chinese patent CN1065261A disclose a bimetallic composite carbon-supported catalyst, wherein the bimetal is formed by a composite of at least one Group VIII metal and copper, wherein copper accounts for 12-22% of the total mass of the catalyst; the bimetallic
  • the composite catalyst can be used in the hydrodechlorination reaction of CFC-113, but the reaction products are chlorotrifluoroethylene and trifluoroethylene or tetrafluoroethylene, and chlorotrifluoroethylene cannot be selectively obtained.
  • European patent EP0416615A1 discloses that Fe, Ni, Cu, Sn, Zn, Cr or their oxides are used as catalyst active components, silica, magnesia, alumina, zirconia, Y-type zeolite, silica-alumina , silicon carbide, diatomaceous earth, etc. as the carrier catalyst, the catalyst can be used in the hydrodechlorination of CFC-113 to prepare chlorotrifluoroethylene, but the catalyst uses different active components or carriers. Only about 80%, which makes the application of this catalyst have certain limitations.
  • Chinese patent CN1351903A discloses a kind of quaternary compound with precious metal ruthenium or palladium or platinum and copper as the main active components, adding lanthanum-rich mixed rare earth or metal lanthanum, alkali metal lithium as modification aids, and coconut shell activated carbon as the carrier Catalyst, the life of the catalyst is about 600 hours, but in the absence of upgrading aids, the selectivity of the catalyst is only 70-80%, and the method provided by this patent is compared in the selection of active components and upgrading aids Limited.
  • Chinese patent CN105457651B discloses a hydrodechlorination catalyst with Pd and Cu as the main catalyst, at least one of Mg, Ca, Ba, Co, Mo, Ni, Sm and Ce as the auxiliary agent and supported on activated carbon , the catalyst can be used for CFC-113 catalytic hydrodechlorination to prepare chlorotrifluoroethylene, the conversion rate can reach 95%, the selectivity is 95%, and the catalyst life is 2000 hours.
  • hydrodechlorination catalysts all have low catalytic activity and poor stability. When applied to the hydrodechlorination reaction, the problem of low reaction selectivity generally exists. Therefore, a high activity, high selectivity, and stable New catalysts with high performance are particularly important.
  • the present invention proposes three core-shell hydrodechlorination catalysts with high activity and high stability, which can significantly improve the selectivity of products when applied to the hydrodechlorination of chlorofluoroalkanes.
  • the present invention provides a first core-shell structure hydrodechlorination catalyst, which is specifically as follows:
  • a core-shell structure hydrodechlorination catalyst the catalyst comprises:
  • the carrier is a monolithic activated carbon carrier
  • the active metal supported on the carrier is selected from at least one of palladium, platinum, iridium and nickel;
  • the second metal supported on the carrier, the second metal is selected from one of copper, tin, silver, and zinc;
  • the catalyst has an encapsulated structure, the core is the active metal, and the shell is the second metal.
  • the active metal and the second metal in the catalyst are supported on the carrier, they are in the form of ions, respectively, or both form an alloy, while the active metal and the second metal in the catalyst of the present invention mainly exist in the form of simple substances, and the active metal is in the form of The elemental form becomes the core part, the second metal forms the shell part in the elemental form, the active metal and the second metal form the encapsulated bimetallic particles, and the non-encapsulated particles exist in the form of single metal particles or alloy particles of the active metal and the second metal .
  • the loading amount of the active metal is 0.05-5.0%
  • the loading amount of the second metal is 0.01-4.0%
  • the loading amount of the second metal is not higher than that of the active metal.
  • the supported amount of the active metal is 0.1-4.0%
  • the supported amount of the second metal is 0.05-3.0%.
  • the mass ratio of the active metal to the second metal is 1-6:1.
  • the mass ratio of the active metal to the second metal is 1.5-4.5:1.
  • the size of the active metal particles in the core part is less than or equal to 90 nm, and the thickness of the shell layer is less than or equal to 5 nm.
  • the size of the active metal particles in the core part is less than or equal to 60 nm, and the thickness of the shell layer is less than or equal to 3.5 nm.
  • the core-shell structure hydrodechlorination catalyst of the present invention adopts a monolithic activated carbon carrier, and the material of the monolithic activated carbon carrier is selected from coconut shell, wood or coal activated carbon.
  • the monolithic activated carbon carrier can improve the fluidity of the fluid in the catalyst and improve the catalytic efficiency.
  • the specific surface area of the monolithic activated carbon carrier is greater than or equal to 900 m 2 /g, the ash content is less than or equal to 3.0 wt %, the pore density is 10-50 pores/cm 2 , and the density is 0.1-0.8 g/mL.
  • the specific surface area is greater than or equal to 1100 m 2 /g, the ash content is less than or equal to 2.0 wt %, the pore density is 15-45 pores/cm 2 , and the density is 0.3-0.6 g/mL.
  • the conventional catalyst preparation method cannot obtain the encapsulated catalyst structure.
  • the present invention provides a preparation method of a core-shell structure hydrodechlorination catalyst, and the preparation method comprises the following steps:
  • the monolithic activated carbon carrier is immersed in an active metal salt solution to form an immersion solution, immersed at 25 to 85° C. for 2 to 6 hours, then taken out, left to stand and drained, and purged with nitrogen flow;
  • the monolithic activated carbon carrier loaded with active metal ions is immersed in ethylene glycol, and hydrogen is introduced into the ethylene glycol, stirred, and the temperature is controlled to be 20-95°C, the pressure is 0.1-0.5Mpa, and the time is 1-10 hours, the active metal ions are reduced to active metal elements;
  • the reaction temperature is 100 ⁇ 250 °C
  • the reaction pressure is 0.1 ⁇ 2.0Mpa
  • the reaction time is 3 ⁇ 10 hours, after the reaction finishes, take out and drain, and the second metal ion is reduced
  • the second metal element is wrapped outside the active metal element
  • the monolithic activated carbon carrier loaded with the active metal and the second metal is placed in a nitrogen atmosphere, the space velocity is 50-1000h -1 , and the temperature is raised from room temperature at a rate of 0.5-2.0°C/min, and then the temperature is maintained at 110-150°C. drying for 2 to 5 hours to obtain a catalyst precursor;
  • the catalyst precursor is placed in a hydrogen atmosphere, heated to 250-450°C at a rate of 0.1-2.0°C/min, and kept at a constant temperature for 1-5 hours to obtain the hydrodechlorination catalyst.
  • the impregnation of the active metal in step A1 is carried out under stirring, the impregnation temperature is 30-75° C., the impregnation time is 2.5-5 hours, and the volume ratio of the total volume of the impregnation solution to the monolithic activated carbon carrier is 2 ⁇ 5:1.
  • the active metal-loaded monolithic activated carbon carrier taken out in the A1 step is allowed to stand for 10 to 20 hours in an environment of 20 to 35 ° C and an air humidity of ⁇ 80%, drained, and then the flow rate is 0.1 to 2.0 m/ s. Purging in a nitrogen stream containing 0.1-1.0v/v% oxygen for 0.5-2 hours.
  • the temperature is controlled at 50-90°C, the pressure is 0.2-0.4Mpa, and the time is 2-5 hours; in the reduction process of the second metal particles in step A2, the reaction temperature is controlled at 150-220°C, The reaction pressure is 0.5-1.5Mpa, and the reaction time is 4-8 hours.
  • the hydrogen gas is introduced into the ethylene glycol from the bottom of the reactor through a gas distributor to stir the reaction.
  • the reactor is preferably a tank type reactor, a magnet is placed at the bottom for stirring reaction, and the monolithic activated carbon carrier loaded with active metal is placed above the magnet.
  • the active metal salt solution is an active metal nitrate solution or an active metal chloride solution.
  • the active metal salt solution is a metal chloride solution, such as nickel chloride solution, and a complex solution formed by chloride ion and noble metal, such as [PdCl 4 ] 2- , [PtCl 4 ] 2- , [IrCl ] 4 ] 2- .
  • the second metal salt solution is a second metal nitrate solution or a second metal chloride solution, and the solution concentration is 0.5-2.0 mol/L.
  • the second metal salt solution is selected from at least one of silver nitrate, zinc chloride, and copper nitrate, and the solution concentration is 0.5-1.5 mol/L.
  • the space velocity is 100-500 h -1
  • the heating rate is 0.75-1.75 °C/min
  • constant temperature drying is performed for 2.5-4.5 hours to obtain a catalyst precursor
  • the space velocity is 100 ⁇ 500h -1
  • the temperature is raised to 275-400°C at a rate of 0.2-1.75°C/min, and the temperature is kept constant for 2-4 hours to obtain the hydrodechlorination catalyst.
  • the hydrodechlorination catalyst prepared according to the method of the present invention ⁇ 85% of the second metal particles are in the encapsulated bimetallic structure, and the rest are in the state where the two metal particles are dispersed or embedded in each other. More preferably, in the hydrodechlorination catalyst prepared by the preparation method of the present invention, ⁇ 90% of the second metal particles are in an encapsulated bimetallic structure.
  • the active metal of the present invention has strong hydrogen dissociation performance. After the ethylene glycol impregnation solution is filled with hydrogen, the hydrogen is dissociated into active hydrogen on the active metal particles, and the second metal ions are induced on the surface of the active metal particles. reduction to form a wrapping structure. After the initial wrapping structure is formed, the hydrogen dissociation performance will decrease, and the second metal will gradually be further deposited. Therefore, the present invention further adopts ethylene glycol as the immersion liquid, and ethylene glycol can exhibit reducibility at high temperature, so as to solve the problem that the second metal deposition difficulty gradually increases, so that the second metal can continue to be deposited outside the active metal. Under the combined action of ethylene glycol impregnation solution and hydrogen, the encapsulated core-shell structure hydrodechlorination catalyst was realized.
  • the present invention also provides the application of any of the above-mentioned core-shell structure hydrodechlorination catalysts, and the catalyst can be used for trifluorotrichloroethane, 1,1,2-trichloro-fluoroethane, 1,2-
  • the hydrodechlorination reaction of fluorochloroalkanes such as dichlorotetrafluoroethane can also be used for 2,3-dichloro-1,1,1,4,4,4-hexafluoro-2-butene (CFO-1316 ) and other hydrodechlorination of chlorofluoroalkenes.
  • the present invention also provides a continuous preparation method of chlorotrifluoroethylene, and the continuous preparation method comprises the following steps:
  • the molar ratio of the trifluorotrichloroethane to hydrogen is: 1:1-4, preferably 1:1-3.
  • reaction temperature is 150-300°C
  • the raw material space velocity is 10-1300 h -1 ; preferably, the reaction temperature is 160-280°C, and the raw material space velocity is 10-1100 h -1 .
  • the present invention provides a second core-shell structure hydrodechlorination catalyst, which is specifically as follows:
  • a monolithic cordierite supported hydrodechlorination catalyst comprising:
  • the carrier is a monolithic cordierite carrier
  • the active metal supported on the carrier is selected from at least one of palladium, platinum, iridium and nickel;
  • the second metal supported on the carrier, the second metal is selected from one of copper, tin, silver, and zinc;
  • the catalyst is an encapsulated bimetallic particle with a core-shell structure, the core is an active metal, and the shell is a second metal.
  • the active metal and the second metal in the catalyst are supported on the carrier, they are in the form of ions, respectively, or both form an alloy, while the active metal and the second metal in the catalyst of the present invention mainly exist in the form of simple substances, and the active metal is in the form of The elemental form becomes the core part, the second metal forms the shell part in the elemental form, the active metal and the second metal form bimetallic particles, and the uncoated particles exist in the form of active metal single metal particles and second metal single metal particles or alloy particles .
  • the monolithic cordierite carrier is a nitrogen-doped carbon-coated monolithic cordierite carrier
  • the mass of the nitrogen-doped carbon coating accounts for 0.1-5.0 wt % of the monolithic cordierite carrier
  • the nitrogen content accounts for 0.1-5.0 wt % of the carbon-coated monolithic cordierite carrier.
  • 0.1 to 8.0 wt% of the mass of the layer More preferably, the mass of the nitrogen-doped carbon coating accounts for 0.2-4.0 wt % of the monolithic cordierite carrier, and the nitrogen content accounts for 0.15-7.0 wt % of the mass of the carbon coating.
  • the pore density of the monolithic cordierite carrier is 10-50 pores/cm 2 , and the specific surface area is ⁇ 900 m 2 /g.
  • the pore density of the monolithic cordierite carrier is 13-48 pores/cm 2 , and the specific surface area is greater than or equal to 1100 m 2 /g.
  • the coating method of the nitrogen-doped carbon coating on the surface of the nitrogen-doped carbon-coated monolithic cordierite carrier of the present invention comprises the following steps:
  • the starch, glucose, ethylenediamine and water are prepared into an aqueous solution in a mass ratio of 1:1 ⁇ 3:1 ⁇ 3:1 ⁇ 2, the monolithic cordierite carrier is immersed in it, and the surface of the monolithic cordierite carrier is evenly coated Then take it out, dry at 110-150°C for 2-3 hours at a constant temperature, and then calcinate at 400-800°C for 3-8 hours in a nitrogen atmosphere to obtain a nitrogen-doped carbon-coated monolithic cordierite carrier.
  • the loading of the active metal is 0.01-4.5%
  • the loading of the second metal is 0.01-5.5
  • the loading of the second metal is not lower than active metals.
  • the supported amount of the active metal is 0.05-4.5%
  • the supported amount of the second metal is 0.05-5.0%.
  • the mass ratio of the active metal to the second metal is 1:1-5.
  • the mass ratio of the active metal to the second metal is 1:2 to 1:5.
  • the size of the active metal particles in the core part is ⁇ 100 nm, and the thickness of the shell layer is ⁇ 5 nm.
  • the size of the active metal particles in the core portion is less than or equal to 80 nm, and the thickness of the shell layer is less than or equal to 4.8 nm.
  • the monolithic cordierite carrier hydrodechlorination catalyst of the present invention adopts monolithic cordierite carrier. Compared with the conventional activated carbon carrier, the monolithic cordierite carrier can improve the fluidity of fluid in the catalyst and improve the catalytic efficiency.
  • the present invention adopts the monolithic cordierite carrier coated with nitrogen-doped carbon, which can effectively regulate the organizational structure of the carrier and the chemical composition of the surface, and further enhance the catalytic activity and stability of the carrier surface.
  • the conventional catalyst preparation method cannot obtain the encapsulated catalyst structure.
  • the present invention proposes a preparation method of a monolithic cordierite carrier hydrodechlorination catalyst, and the preparation method comprises the following steps:
  • the nitrogen-doped carbon-coated monolithic cordierite carrier is dipped into the dipping solution formed by the active metal salt solution, dipped at 25 to 85 ° C for 2 to 6 hours, taken out, left to drain, and purged with nitrogen flow;
  • the reaction temperature is 150 ⁇ 350 °C
  • the reaction pressure is 0.5 ⁇ 4.0Mpa
  • the reaction time is 3 ⁇ 10 hours
  • the reaction finishes take out and drain
  • the second metal ion is reduced
  • the second metal element is wrapped outside the active metal element
  • the monolithic cordierite carrier loaded with the active metal and the second metal is placed under a nitrogen atmosphere, and the temperature is raised from room temperature at a rate of 0.5 to 2.0 °C/min, and then dried at a constant temperature of 110 to 150 °C for 2 to 5 hours to obtain a catalyst.
  • precursor
  • the catalyst precursor is placed in a hydrogen atmosphere, the space velocity is not less than 100h -1 , the temperature is raised to 250-450°C at a rate of 0.1-2.0°C/min, and the temperature is kept constant for 1-5 hours to obtain the hydrodechlorination catalyst. .
  • the impregnation of the active metal in step A1 is carried out under stirring, the impregnation temperature is 35-70° C., the impregnation time is 3-5 hours, and the volume ratio of the total volume of the impregnation solution to the monolithic cordierite carrier is 2 to 5:1.
  • the monolithic cordierite carrier loaded with active metal taken out in step A1 is left standstill for 10 to 20 hours in an environment of 20-35 ° C and air humidity ⁇ 80%, drained, and then the flow rate is 0.1-2.0 m. /s, purging in a nitrogen stream containing 0.1-1.0v/v% oxygen for 0.5-2 hours.
  • the control temperature is 60-90°C
  • the pressure is 0.1-0.15Mpa
  • the time is 2-5 hours
  • the reaction temperature is 250-350°C
  • the reaction pressure is 0.5-3.5MPa
  • the reaction time is 5-7 hours.
  • the hydrogen gas is introduced into the ethylene glycol from the bottom of the reactor through a gas distributor to stir the reaction.
  • the reactor is preferably a tank type reactor, a magnetron is placed at the bottom for stirring the reaction, and the monolithic cordierite carrier loaded with active metal ions is placed above the magneton.
  • the active metal salt solution is an active metal nitrate solution or an active metal chloride solution.
  • the active metal salt solution is a metal chloride solution, such as nickel chloride solution, and a complex solution formed by chloride ion and noble metal, such as [PdCl 4 ] 2- , [PtCl 4 ] 2- , [IrCl ] 4 ] 2- .
  • the second metal salt solution is a second metal nitrate solution or a second metal chloride solution, and the solution concentration is 0.5-2.0 mol/L.
  • the second metal salt solution is selected from at least one of silver nitrate, zinc chloride, and copper nitrate, and the solution concentration is 1.0-1.5 mol/L.
  • the heating rate is 1.0-1.5°C/min, and after reaching 120-140°C, constant temperature drying is performed for 2.5-4.8 hours to obtain a catalyst precursor;
  • the temperature is raised to 300-400°C at a rate of 1.5°C/min, and the temperature is kept constant for 2-3.8 hours to obtain the hydrodechlorination catalyst.
  • hydrodechlorination catalyst prepared by the method of the present invention ⁇ 90% of the active metal particles are in the encapsulated bimetallic structure, and the other are in the state where the two metal particles are dispersed or embedded in each other. More preferably, in the hydrodechlorination catalyst prepared by the preparation method of the present invention, ⁇ 95% of the active metal particles are in an encapsulated bimetallic structure.
  • the active metal of the present invention has strong hydrogen dissociation performance. After the ethylene glycol impregnation solution is filled with hydrogen, the hydrogen is dissociated into active hydrogen on the active metal particles, and the second metal ions are induced on the surface of the active metal particles. reduction to form a wrapping structure. After the initial wrapping structure is formed, the hydrogen dissociation performance will decrease, and the second metal will gradually be further deposited. Therefore, the present invention further adopts ethylene glycol as the immersion liquid, and ethylene glycol can exhibit reducibility at high temperature, so as to solve the problem that the second metal deposition difficulty gradually increases, so that the second metal can continue to be deposited outside the active metal. Under the combined action of ethylene glycol impregnation solution and hydrogen, the encapsulated monolithic cordierite supported hydrodechlorination catalyst was realized.
  • the present invention also provides the application of any one of the above monolithic cordierite supported hydrodechlorination catalysts, and the catalyst can be used for trifluorotrichloroethane, 1,1,2-trichloro-fluoroethane, 1,2 -Hydrodechlorination of chlorofluoroalkanes such as dichlorotetrafluoroethane, also can be used for 2,3-dichloro-1,1,1,4,4,4-hexafluoro-2-butene (CFO- 1316) and other hydrodechlorination of chlorofluoroalkenes.
  • the catalyst can be used for trifluorotrichloroethane, 1,1,2-trichloro-fluoroethane, 1,2 -Hydrodechlorination of chlorofluoroalkanes such as dichlorotetrafluoroethane, also can be used for 2,3-dichloro-1,1,1,4,4,4-hexafluoro-2
  • the present invention also provides a continuous preparation method of chlorotrifluoroethylene, the preparation method comprises the following steps:
  • chlorotrifluoroethylene is prepared by using trifluorotrichloroethane and hydrogen as raw materials through a hydrodechlorination reaction.
  • the molar ratio of the trifluorotrichloroethane to hydrogen is 1:1-4, preferably 1:1-3.5.
  • reaction temperature is 150-300°C
  • the raw material space velocity is 10-1500 h -1 ; preferably, the reaction temperature is 170-280°C, and the raw material space velocity is 10-1200 h -1 .
  • the present invention provides a hydrodechlorination catalyst with a third core-shell structure, which is specifically as follows:
  • a highly selective hydrodechlorination catalyst comprising:
  • the active metal supported on the carrier is selected from at least one of palladium, platinum, iridium and nickel;
  • the second metal supported on the carrier, the second metal is selected from one of copper, tin, silver, and zinc;
  • the catalyst is mainly encapsulated bimetallic particles with a core-shell structure, the core is an active metal, the shell is a second metal, the active metal and the second metal form encapsulated bimetallic particles, and the non-encapsulated particles are made of active metal.
  • the single metal particles and the second metal exist in the form of single metal particles or alloy particles.
  • the active metal and the second metal in the catalyst are supported on the carrier, they are in the form of ions, or both form an alloy, while the active metal and the second metal in the catalyst of the present invention are both in the form of elemental substances, and the active metal is in the form of The elemental form becomes the core part, the second metal forms the shell part in the elemental form, and the active metal and the second metal form bimetallic particles.
  • the loading amount of the active metal is 0.05-5.0%
  • the loading amount of the second metal is 0.1-8.0%
  • the loading amount of the second metal is not lower than that of the active metal.
  • the supported amount of the active metal is 0.1-4.5%
  • the supported amount of the second metal is 0.1-5.0%.
  • the mass ratio of the active metal to the second metal is 1:1-6.
  • the mass ratio of the active metal to the second metal is 1:1-5.
  • the size of the active metal particles in the core part is ⁇ 65 nm, and the thickness of the shell layer is ⁇ 10 nm.
  • the size of the active metal particles in the core portion is less than or equal to 55 nm, and the thickness of the shell layer is less than or equal to 8.0 nm.
  • the carrier of the high-selectivity hydrodechlorination catalyst of the present invention is granular activated carbon or columnar activated carbon, and the material is selected from coconut shell, wood or coal-based activated carbon.
  • the specific surface area of the activated carbon carrier is greater than or equal to 1000 m 2 /g, and the ash content is less than or equal to 3.0 wt %. More preferably, the specific surface area of the activated carbon carrier is greater than or equal to 1100 m 2 /g, and the ash content is less than or equal to 2.8 wt %.
  • the conventional catalyst preparation method cannot obtain the encapsulated catalyst structure.
  • the present invention proposes a preparation method of a high-selectivity hydrodechlorination catalyst with a core-shell structure, and the preparation method comprises the following steps:
  • the immersion solution of active metal salt is prepared according to the load, immersed at 25-95°C under ultrasonic for 0.5-10 hours, and then centrifuged to obtain active metal particles;
  • the dipping solution is ethylene glycol aqueous solution, formalin solution or glucose aqueous solution. at least one;
  • the active metal particles and the second metal salt solution configured according to the load are added to the reducing reagent aqueous solution, and hydrogen is introduced under stirring, the hydrogen pressure is 0.1-2.0 MPa, the temperature is controlled at 100-300 ° C, and centrifugation is performed after 1-10 hours, Obtain encapsulated bimetallic particles;
  • the encapsulated bimetallic particles are placed in deionized water, an activated carbon carrier is added under agitation, immersed, filtered and washed to obtain activated carbon supported bimetallic particles; the immersion temperature is 20-80° C., and the immersion time is 1-10 hours ;
  • the activated carbon-supported bimetallic particles are placed in a nitrogen atmosphere, and the temperature is raised from room temperature at a rate of 0.5 to 2.0 °C/min, and then dried at a constant temperature of 110 to 150 °C for 2 to 5 hours to obtain a catalyst precursor;
  • the catalyst precursor is placed in a hydrogen atmosphere, heated to 250-450°C at a rate of 0.1-2.0°C/min, and kept at a constant temperature for 1-5 hours to obtain the hydrodechlorination catalyst.
  • immersion and reduction are carried out under ultrasonication, so that the system is uniformly dispersed and the agglomeration of active metals is avoided.
  • the ultrasonic frequency is 30-50kHz, and the power is 300-1000w.
  • the active metal salt is active metal nitrate or active metal chloride, more preferably active metal chloride, such as nickel chloride, and a complex formed by chloride ion and precious metal, such as [ PdCl 4 ] 2- , [PtCl 4 ] 2- , [IrCl 4 ] 2- .
  • the mass content of one or more of the ethylene glycol aqueous solution, the formalin aqueous solution or the glucose aqueous solution as the immersion liquid is 1 to 20 wt %, more preferably 2 to 18 %.
  • the immersion temperature is 35 ⁇ 80°C, and the immersion time is 2 ⁇ 8h. After immersion, centrifugal separation is adopted, and the obtained active metal particles are washed to neutrality with deionized water.
  • the step A2 hydrogen is introduced into the reducing reagent under stirring, preferably, the hydrogen is introduced from the bottom of the reactor through a gas distributor; the reaction
  • the reactor is preferably a tank-type reactor, and a magnet is placed at the bottom for stirring, and the stirring speed is preferably 1000-3000 r/min.
  • the second metal salt solution is a second metal nitrate solution or a second metal chloride solution, and the solution concentration is 0.1-2.0 mol/L; the reducing reagent is at least one of ethylene glycol, sodium borohydride or hydrazine hydrate.
  • the solution is an aqueous solution with a mass content of 5-50 wt %, and the mass ratio of the reducing agent to the second metal is 1:20-100. More preferably, the reducing agent aqueous solution is an aqueous solution of ethylene glycol, sodium borohydride or hydrazine hydrate with a mass content of 10-40 wt %, and the mass ratio of the reducing agent to the second metal is 1:30-90.
  • the hydrogen pressure is preferably 0.2-1.8 MPa
  • the temperature is controlled at 150-250° C.
  • the reaction is performed for 2-5 hours. After the reaction was completed, centrifugation was performed, and the obtained encapsulated bimetallic particles were washed with deionized water until neutral.
  • step A3 the encapsulated bimetallic particles are first placed in deionized water, ultrasonicated for 5-20 minutes, and stirred for 1-3 hours to make the bimetallic particles uniformly dispersed, and then Activated carbon carrier is added under stirring, and the stirring speed is 1000-3000 r/min.
  • the ratio of the volume of the activated carbon carrier to the total volume of the impregnation solution is 1:1 to 5, and the preferred volume ratio is 1:2 to 4.5.
  • the bimetallic particles are uniformly loaded on the activated carbon carrier, they are filtered and washed to neutrality, and further drying and reduction are required.
  • the heating rate is 0.8-1.8°C/min.
  • constant temperature drying is performed for 2.5-4.5 hours, and the space velocity is greater than 100h -1 to obtain a catalyst precursor; in step A5, The temperature is raised to 280-430° C. at a rate of 0.2-1.9° C./min, the temperature is kept constant for 1-4 hours, and the space velocity is greater than 100 h ⁇ 1 to obtain the hydrodechlorination catalyst.
  • the highly selective hydrodechlorination catalyst prepared according to the method of the present invention ⁇ 80% of the active metal particles are in the encapsulated bimetallic structure, and the rest are in the state where the two metal particles are dispersed or embedded in each other. More preferably, in the hydrodechlorination catalyst prepared by the preparation method of the present invention, ⁇ 85% of the active metal particles are in an encapsulated bimetallic structure.
  • the active metal of the present invention has strong hydrogen dissociation performance, and hydrogen gas will dissociate into active hydrogen on the active metal particle, and induce the reduction of the second metal ion on the surface of the active metal particle, thereby forming a wrapping structure.
  • the hydrogen dissociation performance will be reduced, which gradually increases the difficulty of further deposition of the second metal. Therefore, the present invention further adopts the aqueous solution of ethylene glycol, sodium borohydride or hydrazine hydrate as the reducing agent, and the reducing agent can show reducibility at high temperature, so as to solve the problem that the difficulty of depositing the second metal gradually increases, so that the second metal is difficult to deposit. Metal can continue to deposit outside the active metal.
  • the invention realizes the preparation of the encapsulated high-selectivity hydrodechlorination catalyst under the combined action of the reducing agent and hydrogen.
  • the present invention also provides the application of any of the above-mentioned high-selectivity hydrodechlorination catalysts, and the catalyst can be used for trifluorotrichloroethane, 1,1,2-trichloro-fluoroethane, 1,2-dichloroethane Hydrodechlorination of fluorochloroalkanes such as chlorotetrafluoroethane, can also be used for 2,3-dichloro-1,1,1,4,4,4-hexafluoro-2-butene (CFO-1316) Hydrodechlorination of chlorofluoroalkenes.
  • the present invention also provides a continuous preparation method of chlorotrifluoroethylene, the preparation method comprises the following steps:
  • chlorotrifluoroethylene is prepared by using trifluorotrichloroethane and hydrogen as raw materials through a hydrodechlorination reaction.
  • the molar ratio of the trifluorotrichloroethane to hydrogen is 1:1-4, preferably 1:1-3.5.
  • reaction temperature is 150-300°C
  • the raw material space velocity is 10-1200 h -1 ; preferably, the reaction temperature is 180-290°C, and the raw material space velocity is 10-900 h -1 .
  • the beneficial effects of the present invention include:
  • the three catalysts of the present invention are all core-shell structures, the core part is an active metal, and the shell part is a second metal, forming a wrapped bimetallic structure, and electrons are shifted between the two metal structures, which modulates hydrogen.
  • the dissociation performance and carbon-chlorine bond (C-Cl) activation performance make the catalyst have high activity and high stability.
  • the first catalyst of the present invention adopts a monolithic activated carbon carrier, which reduces the pressure drop of the catalyst bed, improves the fluidity of the fluid in the catalyst, thereby improves the catalytic efficiency and the stable operation time of the catalytic reaction, and solves the problem of granular catalysts.
  • the problem that the powder is easy to block the bed.
  • the second catalyst of the present invention adopts a monolithic cordierite carrier, which reduces catalyst lamination, improves the fluidity of fluid in the catalyst, and then improves catalytic efficiency; and the monolithic cordierite carrier is nitrogen-doped
  • the carbon-coated monolithic cordierite carrier can effectively regulate the organizational structure and surface chemical composition of the carrier, and further enhance the catalytic activity and stability of the carrier surface.
  • Fig. 1 is the TEM characterization diagram of the core-shell structure hydrodechlorination catalyst prepared in Example 1.1 of the present invention
  • Fig. 2 is the TEM characterization diagram of the monolithic cordierite-supported hydrodechlorination catalyst prepared in Example 2.1 of the present invention
  • Figure 3 is a TEM characterization diagram of the highly selective hydrodechlorination catalyst prepared in Example 3.1 of the present invention.
  • Active metal loading Rinse the monolithic activated carbon carrier (coal, 1000 m 2 /g, 2.0 wt% ash, 30 pore/cm 2 , density 0.5 g/mL) with deionized water, then immerse it in In the chloropalladium acid aqueous solution, the palladium content is 1.0% of the monolithic activated carbon carrier, and the volume ratio of the total volume of the impregnation solution to the monolithic activated carbon carrier is 2:1.
  • Second metal loading 1) Active metal reduction: place the active metal-loaded monolithic activated carbon carrier purged with nitrogen flow in a high-pressure reactor, immerse it in ethylene glycol solution, and add magnetrons to the bottom of the autoclave. During stirring (1500r/min of revolutions), hydrogen was continuously introduced into the ethylene glycol solution, and the temperature was raised to 80°C for 5 hours, and the reaction pressure was 0.1MPa; 2) the second metal load: the temperature was raised to 180°C, Increase the pressure to 1.0 MPa, and according to the load of 1.0%, pipette 1 mol/L cupric chloride solution, drop it into the autoclave through a constant pressure funnel, and continue the constant temperature reaction for 5 hours.
  • the monolithic activated carbon carrier loaded with the active metal and the second metal is placed in a tube furnace, and in a nitrogen atmosphere (the space velocity is 300 h -1 ), the temperature is increased from room temperature to 120 °C at a rate of 0.5 °C/min. °C, constant temperature drying for 5 hours to obtain the catalyst precursor.
  • the obtained catalyst precursor is heated from room temperature to 350° C. at a rate of 0.1° C./min under a hydrogen atmosphere (space velocity is 300 h ⁇ 1 ), and kept at a constant temperature for 5 hours to obtain the hydrodechlorination catalyst, Record it as cat1.1.
  • Figure 1 shows the TEM characterization diagram of the hydrodechlorination catalyst prepared in this embodiment.
  • the hydrodechlorination catalyst of this embodiment forms a packaged structure, the core is palladium, and the shell is copper.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, except that the material of the monolithic activated carbon carrier adopts wood instead of coal to prepare a hydrodechlorination catalyst, which is denoted as cat1.2.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, except that the specific surface area of the monolithic activated carbon carrier is 1200 m 2 /g, the ash content is 1.8 wt%, the pore density is 20 pores/cm 2 , and the density is 0.6 g/mL.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.3.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, except that the loading of the active metal palladium is 1.5%, and the loading of the second metal copper is 1.0%.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.4.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, except that the loading of the active metal palladium is 2.5%, and the loading of the second metal copper is 0.05%.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.5.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, the only difference is that platinum is used as the active metal, zinc is used as the second metal, and the loadings of the active metal and the second metal are unchanged.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.6.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, the only difference is that nickel is used as the active metal, zinc is used as the second metal, and the loadings of the active metal and the second metal are unchanged.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.7.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, except that the active metal solution adopts palladium nitrate instead of chloropalladic acid, the second metal solution adopts zinc chloride to replace copper chloride, and the loadings of active metal and second metal are unchanged.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.8.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, except that the active metal solution is chloropalladic acid, the second metal solution uses zinc nitrate instead of copper chloride, and the loadings of the active metal and the second metal are unchanged.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.9.
  • step S1 The operation of this example is the same as that of Example 1.1, except that in step S1, the volume ratio of the total volume of the impregnating liquid to the monolithic activated carbon carrier is changed to 5:1.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.10.
  • step S1 The operation of this example is the same as that of Example 1.1, except that in step S1, the volume ratio of the total volume of the impregnating solution to the monolithic activated carbon carrier is 1:1.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.11.
  • step S1 The operation of this example is the same as that of Example 1.1, except that in step S1, the immersion temperature is changed to 75°C.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.12.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, except that in step S1, the immersion time is changed to 5 hours.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.13.
  • step S1 the taken out monolithic activated carbon carrier loaded with active metal is allowed to stand at 20°C.
  • the hydrodechlorination catalyst was prepared and recorded as cat1.14.
  • step S1 the taken out monolithic activated carbon carrier loaded with active metal is allowed to stand in an environment with an air humidity of 50%.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.15.
  • step S1 the taken out monolithic activated carbon carrier loaded with active metal is left to stand for 20 hours.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.16.
  • step S1 the taken out monolithic activated carbon carrier loaded with active metal is drained and then purged in a 2.0 m/s nitrogen flow.
  • the prepared hydrodechlorination catalyst was recorded as cat1.17.
  • step S1 the extracted monolithic activated carbon carrier loaded with active metal is drained and the nitrogen stream contains 1.0v/v% of oxygen.
  • the hydrodechlorination catalyst was prepared and recorded as cat1.18.
  • step S1 the taken out monolithic activated carbon carrier loaded with active metal is drained and then purged in a nitrogen stream for 2 hours.
  • the hydrodechlorination catalyst was prepared and recorded as cat1.19.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, except that the reduction temperature of the active metal particles in step S2 is 50°C.
  • the hydrodechlorination catalyst was prepared and recorded as cat1.20.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, except that the reduction pressure of the active metal particles in step S2 is 0.5 MPa.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.21.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, except that the reduction time of the active metal Li teacher in step S2 is changed from 5 hours to 2 hours.
  • the hydrodechlorination catalyst was prepared and recorded as cat1.22.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, the only difference is that the reduction temperature of the second metal particles in step S2 is increased to 220°C.
  • the hydrodechlorination catalyst was prepared and recorded as cat1.23.
  • step S2 the reduction pressure of the second metal particles is increased to 1.5Mpa.
  • the hydrodechlorination catalyst was prepared and denoted as cat1.24.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, except that the heating rate in step S3 is increased to 1.75°C/min.
  • the hydrodechlorination catalyst was prepared and recorded as cat1.26.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, the only difference is that the constant temperature in step S3 is increased to 145°C.
  • the prepared hydrodechlorination catalyst was recorded as cat1.27.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, except that the heating rate in step S4 is increased to 1.75°C/min.
  • the prepared hydrodechlorination catalyst was recorded as cat1.29.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, the only difference is that the constant temperature in step S4 is reduced to 300°C.
  • the prepared hydrodechlorination catalyst was recorded as cat1.30.
  • Example 1.1 The operation of this example is the same as that of Example 1.1, the only difference is that the constant temperature time in step S4 is reduced to 4 hours.
  • the hydrodechlorination catalyst was prepared and recorded as cat1.31.
  • Example 1.1 The operation of this comparative example is the same as that of Example 1.1, except that the columnar activated carbon is used instead of the monolithic activated carbon carrier, and the prepared catalyst is denoted as B1.1.
  • Example 1.1 The operation of this comparative example is the same as that of Example 1.1, and the difference is only that: the monolithic activated carbon carrier taken out from the dipping solution in step S1 is directly placed in a nitrogen stream for purging, and the process of standing and draining is omitted.
  • the prepared catalyst was designated as B1.2.
  • Example 1.1 The operation of this comparative example is the same as that of Example 1.1, the only difference is that the monolithic activated carbon carrier taken out from the impregnation solution in step S1 is left to stand and drain, without being purged with nitrogen flow, the second metal loading is directly carried out.
  • the prepared catalyst was designated as B1.3.
  • step S2 After passing hydrogen into the ethylene glycol solution, the temperature is directly raised to 180°C, and the pressure is raised to 1.0MPa to carry out the second metal loading, and no active metal is carried out. Restoration steps.
  • the prepared catalyst was designated as B1.4.
  • Example 1.1 The operation of this comparative example is the same as that of Example 1.1, except that in step S2, hydrogen is only introduced in the active metal reduction step, and the introduction of hydrogen is stopped when the second metal is impregnated.
  • the prepared catalyst was designated as B1.5.
  • this comparative example is the same as that of Example 1.1, the only difference is that when the second metal is loaded in step S2, the reaction at normal temperature and pressure is changed instead of the reaction conditions of 180°C and 1.0MPa.
  • the prepared catalyst was designated as B1.6. According to TEM characterization, in the prepared catalyst, 51% of the second metal particles are in the encapsulated bimetallic structure.
  • this comparative example is the same as that of Example 1.1, except that the carrier is not used in the preparation process of this comparative example, and the specific process includes: adding the chloropalladium acid solution to the ethylene glycol solution, and continuously feeding hydrogen under stirring; Add cupric chloride solution to mix, increase temperature and pressure for reaction; dry at constant temperature under nitrogen atmosphere; reduce under hydrogen atmosphere.
  • the prepared catalyst is denoted as B1.8, and the size of the obtained metal particles is 100-800 nm, and the size distribution is uneven.
  • the monolithic activated carbon carrier (coal quality, 1000 m 2 /g, ash content 2.0wt%, pore density 30 pores/cm 2 , density 0.5g/mL) was rinsed with deionized water, immersed in chloropalladium acid and chlorinated In the copper aqueous solution, the contents of palladium and copper are 1.0% and 1.0% of the monolithic activated carbon carrier, and the volume ratio of the total volume of the impregnation solution to the monolithic activated carbon carrier is 2:1.
  • the stirring was started, the temperature was raised to 50°C, and the mixture was immersed for 3 hours and taken out. It was left standing for 15 hours at 30° C. and air humidity 70% to drain, and then purged with a nitrogen flow (containing 0.1 v/v oxygen) at a flow rate of 0.5 m/s for 1 hour.
  • the prepared catalyst was denoted as B1.9, and the TEM characterization showed that the palladium-copper bimetal did not form a wrapped core-shell structure and was in the state of a bimetallic alloy.
  • the present embodiment is the application of hydrodechlorination catalyst in the reaction of preparing chlorotrifluoroethylene by hydrodechlorination of trifluorotrichloroethane, and the specific steps are as follows:
  • Example 1.1 5g of Cat1.1 prepared in Example 1.1 was put into a fixed bed reactor, and the inner diameter of the reactor was 10 mm. The temperature was raised to 250°C, a mixture of hydrogen and trifluorotrichloroethane with a molar ratio of 1:1 was introduced, the space velocity was 300h -1 , and the reaction was carried out at 250°C.
  • the hydrogenation product was analyzed by Agilent 7890A gas chromatography, and the results showed that the conversion rate was 100% and the selectivity of chlorotrifluoroethylene was 99.58%.
  • Examples 1.33-1.71 are the same as those of Example 1.32, except that cat1.2-cat1.31 and catalysts B1.1-B1.9 are used instead of cat1.1 to carry out the hydrodechlorination reaction.
  • Examples 1.72-1.93 are the same as those of Example 1.32, except that Cat1.6 is used as the hydrodechlorination catalyst, and the reaction conditions are changed to carry out the hydrodechlorination reaction.
  • Example 1.94 is a stability experiment performed under the reaction conditions of Example 1.80.
  • Starch glucose, ethylenediamine and water are prepared into an aqueous solution in a mass ratio of 1:2:2:2, the monolithic cordierite carrier is immersed in it, and the monolithic cordierite carrier is evenly coated on the surface and taken out. After drying for 3 hours, it was placed in a nitrogen atmosphere and calcined at 400°C for 5 hours. Under the same conditions, continue to repeat dip coating, drying, and firing.
  • a nitrogen-doped carbon-coated monolithic cordierite carrier was obtained, and the nitrogen-doped carbon-coated monolithic cordierite carrier had a specific surface area of 1270 m 2 /g, and the carbon coating content 4.0wt%, of which nitrogen content is 5.0wt%.
  • the coating conditions of the nitrogen-doped carbon coating were changed to obtain monolithic cordierite carriers with different specific surface areas, carbon contents and nitrogen contents, as shown in Table 4 below:
  • Second metal loading 1) Reduction of active metal ions: place the monolithic cordierite carrier with active metal swept through in the autoclave, immersed in ethylene glycol solution, and magnetically added to the bottom of the autoclave. The sub is used for stirring (the number of revolutions is 1500 r/min), hydrogen is continuously introduced into the ethylene glycol solution, the temperature is raised to 80 °C for 5 hours, and the control pressure is 0.1 MPa; 2) The second metal load: increase the temperature to 250 °C , increase the pressure to 1.0 MPa, and pipette 1 mol/L cupric chloride solution according to 0.08% load, drop it into the autoclave through a constant pressure funnel, and continue the constant temperature reaction for 5 hours.
  • the obtained catalyst precursor is heated from room temperature to 350° C. at a rate of 0.1° C./min under a hydrogen atmosphere (space velocity is 200 h ⁇ 1 ), and kept at a constant temperature for 5 hours to obtain the hydrodechlorination catalyst, Record it as cat2.1.
  • Figure 1 shows the TEM characterization diagram of the hydrodechlorination catalyst prepared in the present embodiment.
  • the hydrodechlorination catalyst of the present embodiment forms a packaged structure, the core is palladium, and the shell is copper.
  • Example 2.1 The operation of this example is the same as that of Example 2.1, the only difference is that the hydrodechlorination catalyst is prepared by using carrier 3 instead of carrier 1, the active metal loading is 0.8%, and the second metal loading is reduced to 1.5%.
  • the catalyst is denoted as cat2.2.
  • Example 2.1 The operation of this example is the same as that of Example 2.1, the only difference is that the hydrodechlorination catalyst is prepared by using carrier 8 instead of carrier 1, the active metal loading is 0.3%, and the second metal loading is reduced to 1.5%.
  • the catalyst is denoted as cat2.3.
  • 90% of the active metal particles in the cat2.3 are encapsulated bimetallic structures.
  • Example 2.1 The operation of this example is the same as that of Example 2.1, the only difference is that the hydrodechlorination catalyst is prepared by using carrier 12 instead of carrier 1, the active metal is platinum, the second metal is changed to zinc, and the prepared catalyst is recorded as cat2.4 .
  • the operation of the present embodiment is the same as that of Example 2.1, the difference is only that: the carrier 18 is used to replace the carrier 1 to carry out the preparation of the hydrodechlorination catalyst, the active metal is changed to nickel, the second metal is changed to zinc, and the catalyst obtained is denoted as cat2. 5.
  • Example 2.1 The operation of this example is the same as that of Example 2.1, the only difference is that the hydrodechlorination catalyst is prepared by using carrier 2 instead of carrier 1, the loading of active metal palladium is 1%, and the loading of second metal copper is 1.5%.
  • the hydrodechlorination catalyst was prepared and denoted as cat2.6.
  • Example 2.1 The operation of this example is the same as that of Example 2.1, except that the carrier 7 is used instead of the carrier 1 to prepare the hydrodechlorination catalyst, the active metal solution (active metal precursor) is palladium nitrate, and the second metal solution is zinc chloride , the prepared catalyst is denoted as cat2.7.
  • Example 2.1 The operation of this example is the same as that of Example 2.1, except that the carrier 4 is used instead of the carrier 1 to prepare the hydrodechlorination catalyst, the active metal solution (active metal precursor) is palladium nitrate, and the second metal solution is zinc nitrate,
  • the prepared catalyst was denoted as cat2.8.
  • Example 2.1 The operation of this example is the same as that of Example 2.1, the difference is only that: the carrier 9 is used instead of the carrier 1 to prepare the hydrodechlorination catalyst, and in step S1, the impregnation temperature is increased to 60 ° C, and the prepared catalyst is recorded as cat2. 9.
  • step S1 the impregnation time is increased to 6 hours, and the prepared catalyst is recorded as cat2.10.
  • step S2 the reduction pressure of active metal ions is 0.2 MPa, and the prepared catalyst is denoted as cat2. 11.
  • the operation of the present embodiment is the same as that of Example 2.1, the difference is only that: the carrier 5 is used to replace the carrier 1 to carry out the preparation of the hydrodechlorination catalyst, and in step S2, the active metal ion is reduced for 3 hours, and the catalyst obtained is denoted as cat2.12.
  • this embodiment is the same as that of embodiment 2.1, the difference is only that: the carrier 5 is used to replace the carrier 1 to carry out the preparation of the hydrodechlorination catalyst, and in step S2, the second metal ion reduction temperature is 200 ° C, and the prepared catalyst is denoted as cat2. 13.
  • the operation of the present embodiment is the same as that of Example 2.1, the difference is only that: the carrier 5 is used to replace the carrier 1 to carry out the preparation of the hydrodechlorination catalyst, and in step S2, the second metal ion reduction pressure is 3.0MPa, and the prepared catalyst is denoted as cat2. 14.
  • step S3 the constant temperature drying time is 3 hours, and the prepared catalyst is recorded as cat2.15.
  • the operation of the present embodiment is the same as that of Example 2.1, the difference is only that: the carrier 14 is used to replace the carrier 1 to carry out the preparation of the hydrodechlorination catalyst, and in step S3, the heating rate is changed to 1.5 ° C/min, and the catalyst obtained is recorded as cat2. 16.
  • step S3 the final temperature of the heating is changed to 140°C, and the prepared catalyst is recorded as cat2.17 .
  • step S4 the final temperature of the heating is changed to 400°C, and the prepared catalyst is recorded as cat2.18 .
  • the operation of the present embodiment is the same as that of Example 2.1, the difference is only that: the carrier 17 is used to replace the carrier 1 to carry out the preparation of the hydrodechlorination catalyst, and in step S4, the heating rate is changed to 1.5 ° C/min, and the catalyst obtained is recorded as cat2. 19.
  • Example 2.1 The operation of this comparative example is the same as that of Example 2.1, except that the columnar activated carbon is used instead of the monolithic cordierite carrier, and the prepared catalyst is denoted as B2.1, and 56% of the active metal particles are in the encapsulated bimetallic structure.
  • Example 2.1 The operation of this comparative example is the same as that of Example 2.1, except that the monolithic cordierite carrier taken out from the dipping solution in step S1 is directly placed in a nitrogen stream for purging, and the standing and draining process is omitted.
  • the prepared catalyst was denoted as B2.2, and 54% of the active metal particles were in the encapsulated bimetallic structure.
  • Example 2.1 The operation of this comparative example is the same as that of Example 2.1, except that the monolithic cordierite carrier taken out from the dipping solution in step S1 is left standing and drained, without being purged with nitrogen flow, and directly carrying out the second metal loading.
  • the prepared catalyst was denoted as B2.3, and 58% of the active metal particles were in the encapsulated bimetallic structure.
  • step S2 The operation of this comparative example is the same as that of Example 2.1, except that in step S2, no hydrogen was introduced into the ethylene glycol solution, the temperature was directly raised to 250 °C, and the pressure was raised to 1.0 MPa to carry out the second metal loading, and no active metal was carried out. Restoration steps.
  • the prepared catalyst was denoted as B2.4, and 15% of the active metal particles were in the encapsulated bimetallic structure.
  • step S2 hydrogen is only introduced in the active metal reduction step, and the introduction of hydrogen is stopped when the second metal is impregnated.
  • the prepared catalyst was denoted as B2.5, and 25% of the active metal particles were in the encapsulated bimetallic structure.
  • this comparative example is the same as that of Example 2.1, the only difference is that when the second metal is loaded in step S2, the reaction at normal temperature and pressure is changed instead of the reaction conditions of 250°C and 1.0MPa.
  • the prepared catalyst was denoted as B2.6, and 43% of the active metal particles were in the encapsulated bimetallic structure.
  • this comparative example is the same as that of Example 2.1, except that methanol is used instead of ethylene glycol solution in step S2, the prepared catalyst is recorded as B2.7, and 31% of the active metal particles are in a packaged bimetallic structure.
  • this comparative example is the same as that of Example 2.1, the only difference is that no carrier is used in the preparation process of this comparative example, and the specific process includes: adding the chloropalladium acid solution into the ethylene glycol solution, and continuously feeding hydrogen under stirring ; Add copper chloride solution to mix, heat up and pressurize reaction; Constant temperature drying under nitrogen atmosphere; Reduction under hydrogen atmosphere.
  • the prepared catalyst is denoted as B2.8, the size of the obtained metal particles is 60-700 nm, the size distribution is uneven, and 23% of the active metal particles are in the encapsulated bimetallic structure.
  • Example 2.1 The operation of this comparative example is the same as that of Example 2.1, except that the monolithic cordierite carrier is prepared without nitrogen doping (ethylenediamine is not added).
  • the prepared catalyst was recorded as B2.9, and 57% of the active metal particles were in the encapsulated bimetallic structure.
  • the monolithic cordierite carrier 4 was rinsed with deionized water, it was immersed in an aqueous solution of chloropalladic acid and copper chloride, the contents of palladium and copper were 1.0% and 1.0% of the monolithic cordierite carrier, and the total volume of the immersion solution was The volume ratio of the monolithic cordierite support was 2:1. Start stirring, raise the temperature to 50°C, and take it out after immersion for 3 hours. It was left standing for 15 hours at 30° C. and air humidity 70% to drain, and then purged for 1 hour with a flow of nitrogen (containing 0.1 v/v oxygen) at a flow rate of 0.5 m/s.
  • nitrogen containing 0.1 v/v oxygen
  • the prepared catalyst was denoted as B2.10, and the TEM characterization showed that the palladium-copper bimetal did not form a wrapped core-shell structure and was in the state of a bimetallic alloy.
  • the present embodiment is the application of hydrodechlorination catalyst in the reaction of preparing chlorotrifluoroethylene by hydrodechlorination of trifluorotrichloroethane, and the specific steps are as follows:
  • Example 2.1 0.5 g of Cat2.1 prepared in Example 2.1 was put into a fixed bed reactor, and the inner diameter of the reactor was 10 mm. The temperature was raised to 250°C, a mixture of hydrogen and trifluorotrichloroethane with a molar ratio of 1:1 was introduced, the space velocity was 300h -1 , and the reaction was carried out at 250°C.
  • the hydrogenation product was analyzed by Agilent 7890A gas chromatography, and the results showed that the conversion was 100% and the selectivity to chlorotrifluoroethylene was 99.58%.
  • Examples 2.22-2.48 are the same as those of Example 2.1, except that the catalysts prepared in Examples 2.2-2.20 and Comparative Examples 2.1-2.10 are used instead of cat2.1 for hydrodechlorination.
  • Examples 2.49-2.72 are the same as those of Example 2.22, and Cat2.3 is used as the hydrodechlorination catalyst, and the reaction conditions are changed to carry out the hydrodechlorination reaction.
  • Example 2.73 is a stability experiment performed under the reaction conditions of Example 2.56.
  • Preparation of active metal particles prepare an aqueous solution of chloroplatinic acid with a loading of 1.5 wt%, add 5.0 wt% of an aqueous ethylene glycol solution, and perform ultrasonic immersion. Centrifugal separation after 1 hour, and washed with deionized water (multiple washings) to neutrality to obtain active metal particles;
  • Second metal particle wrapping adding active metal particles and cupric chloride solution prepared at a loading of 2.0 wt % to a 25 wt % ethylene glycol solution, and the mass ratio of the ethylene glycol to the second metal is 1:30 , the concentration of the second metal salt is 0.1 mol/L; hydrogen is introduced into the stirring state, the stirring speed is 3000 r/min, the hydrogen pressure is maintained at 2.0 MPa, the temperature is controlled at 200 ° C, and centrifuged after 5 hours of reaction, and washed with deionized water (multiple washes) to neutrality to obtain wrapped bimetallic particles;
  • Bimetallic particle loading the packaged bimetallic particles are placed in deionized water, ultrasonicated for 5 minutes, and stirred for 1 hour at a speed of 3000 r/min, and then the activated carbon carrier (wooden , specific surface area 1200m 2 /g, ash content 1.5wt%), the volume ratio of the activated carbon carrier to the volume of the impregnation solution is 1:5, soaked at 80 ° C for 3 hours, filtered, washed with deionized water until neutral, Obtain activated carbon-supported bimetallic particles (sealed preservation);
  • the activated carbon-supported bimetallic particles are placed in a tube furnace, and in a nitrogen atmosphere (space velocity is 300h -1 ), the temperature is increased from room temperature to 150°C at a rate of 0.5°C/min, and dried at a constant temperature for 2 hours. catalyst precursor.
  • the obtained catalyst precursor is heated under a hydrogen atmosphere (space velocity is 300h -1 ) from room temperature to 250°C at a rate of 0.1°C/min, and kept at a constant temperature for 1 hour to obtain the hydrodechlorination catalyst, Record it as cat3.1.
  • Figure 1 shows the TEM characterization diagram of the hydrodechlorination catalyst prepared in the present embodiment.
  • the hydrodechlorination catalyst of the present embodiment forms a packaged structure, the core is palladium, and the shell is copper.
  • Example 3.1 The operation of this example is the same as that of Example 3.1, except that the active metal loading is reduced to 1.0% and the second metal loading is reduced to 1.5% to prepare a hydrodechlorination catalyst, denoted as cat3.2.
  • Example 3.1 The operation of this example is the same as that of Example 3.1, the only difference is that the active metal loading is 1.5%, the second metal loading is reduced to 4.5%, and a hydrodechlorination catalyst is prepared, denoted as cat3.3.
  • Example 3.1 The operation of this example is the same as that of Example 3.1, the only difference is that the active metal is platinum, and the second metal is changed to zinc.
  • the hydrodechlorination catalyst was prepared and denoted as cat3.4.
  • Example 3.1 The operation of this example is the same as that of Example 3.1, except that the active metal is changed to nickel, and the second metal is changed to zinc.
  • the hydrodechlorination catalyst was prepared and denoted as cat3.5.
  • Example 3.1 The operation of this example is the same as that of Example 3.1, the difference is only that: the active metal solution (active metal precursor) adopts palladium nitrate, and the second metal solution adopts zinc chloride.
  • the hydrodechlorination catalyst was prepared and denoted as cat3.6.
  • Example 3.1 The operation of this example is the same as that of Example 3.1, except that the active metal solution (active metal precursor) adopts chloropalladium acid, and the second metal solution adopts zinc nitrate.
  • the hydrodechlorination catalyst was prepared and denoted as cat3.7.
  • step S1 The operation of this example is the same as that of Example 3.1, except that in step S1, the immersion temperature is increased to 60°C.
  • the hydrodechlorination catalyst was prepared and recorded as cat3.8.
  • step S1 The operation of this example is the same as that of Example 3.1, except that in step S1, the immersion time is increased to 6 hours.
  • the hydrodechlorination catalyst was prepared and recorded as cat3.9.
  • step S2 when the bimetallic particles are reduced, the hydrogen pressure is 1.5 MPa.
  • the hydrodechlorination catalyst was prepared and recorded as cat3.10.
  • step S2 The operation of this example is the same as that of Example 3.1, except that in step S2, the reduction time of the bimetallic particles is reduced to 3 hours.
  • the hydrodechlorination catalyst was prepared and recorded as cat3.11.
  • step S2 the temperature is 150°C.
  • the hydrodechlorination catalyst was prepared and recorded as cat3.12.
  • step S2 the mass ratio of ethylene glycol to the mass of the second metal is 1:60.
  • the hydrodechlorination catalyst was prepared and recorded as cat3.13.
  • Example 3.1 The operation of this example is the same as that of Example 3.1, except that in step S3, the stirring speed is reduced to 2000 r/min.
  • the hydrodechlorination catalyst was prepared and recorded as cat3.14.
  • step S3 the stirring time is increased to 2 hours.
  • the prepared hydrodechlorination catalyst was recorded as cat3.15.
  • step S3 The operation of this example is the same as that of Example 3.1, the only difference is that: in step S3, ultrasonication is performed for 15 minutes.
  • the hydrodechlorination catalyst was prepared and recorded as cat3.16.
  • step S3 The operation of this example is the same as that of Example 3.1, except that in step S3, the ratio of activated carbon to impregnation solution is 1:3.
  • the hydrodechlorination catalyst was prepared and recorded as cat3.17.
  • Example 3.1 The operation of this example is the same as that of Example 3.1, except that the drying time at the constant temperature in the drying step S4 is increased to 3 hours.
  • the hydrodechlorination catalyst was prepared and recorded as cat3.18.
  • Example 3.1 The operation of this example is the same as that of Example 3.1, except that the heating rate in the drying step of S4 is 1.25°C/min.
  • the hydrodechlorination catalyst was prepared and recorded as cat3.19.
  • step S5 the constant temperature time for reducing the catalyst precursor under a hydrogen atmosphere is increased to 2 hours.
  • the prepared hydrodechlorination catalyst was recorded as cat3.20.
  • step S5 The operation of this example is the same as that of Example 3.1, except that in step S5, the heating rate is 1.0°C/min.
  • the hydrodechlorination catalyst was prepared and recorded as cat3.21.
  • step S5 The operation of this example is the same as that of Example 3.1, except that in step S5, the final temperature is 400°C.
  • the hydrodechlorination catalyst was prepared and recorded as cat3.22.
  • Example 3.1 The operation of this comparative example is the same as that of Example 3.1, except that ultrasonic treatment is not used in the preparation of active metal particles, the prepared catalyst is recorded as B3.1, and 46% of active metal particles have a wrapped bimetallic structure.
  • this comparative example is the same as that of Example 3.1, the only difference is that: during the second metal particle encapsulation process, the temperature was controlled to 80°C, and the prepared catalyst was recorded as B3.2, and 42% of the active metal particles had encapsulated bimetallic structure.
  • this comparative example is the same as that of Example 3.1, except that: during the second metal particle encapsulation process, the temperature is controlled to 350°C, the prepared catalyst is recorded as B3.3, and 51% of the active metal particles are encapsulated bimetallic structures.
  • this comparative example is the same as that of Example 3.1, the only difference is that: in the process of encapsulating the second metal particles, hydrogen is not introduced, the prepared catalyst is recorded as B3.4, and 41% of the active metal particles are in the encapsulated bimetallic structure.
  • this comparative example is the same as that of Example 3.1, except that: in the process of encapsulating the second metal particles, no ethylene glycol solution was added, the prepared catalyst was recorded as B3.5, and 58% of the active metal particles were encapsulated bimetallic structure.
  • this comparative example is the same as that of Example 3.1, except that: in the process of encapsulating the second metal particles, methanol is used instead of ethylene glycol solution, and the prepared catalyst is recorded as B3.6, and 43% of the active metal particles are encapsulated double Metal structure.
  • this comparative example is the same as that of Example 3.1, except that the step of supporting S3 bimetallic particles is omitted, and the prepared catalyst is not supported by a carrier.
  • the prepared catalyst is denoted as B3.7, the size of the obtained metal particles is 70-600 nm, the size distribution is uneven, and 59% of the active metal particles are in the encapsulated bimetallic structure.
  • the activated carbon carrier wood, specific surface area 1200m 2 /g, ash content 1.5wt%) was rinsed with deionized water, then immersed in an aqueous solution of chloropalladic acid and copper chloride, the content of palladium and copper was 1.5% of the activated carbon carrier and 2.0%, the volume ratio of the total volume of the impregnation solution to the activated carbon support was 5:1. Start stirring, heat up to 50°C, soak for 3 hours, take out, and dry at 110°C for 4 hours.
  • the prepared catalyst was denoted as B3.9, and the TEM characterization showed that the palladium-copper bimetal did not form a wrapped core-shell structure and was in the state of a bimetallic alloy.
  • the present embodiment is the application of hydrodechlorination catalyst in the reaction of preparing chlorotrifluoroethylene by hydrodechlorination of trifluorotrichloroethane, and the specific steps are as follows:
  • Example 3.1 0.5 g of Cat3.1 (particle size: 0.5-1 mm) prepared in Example 3.1 was charged into a fixed bed reactor with an inner diameter of 10 mm. The temperature was raised to 250°C, a mixture of hydrogen and trifluorotrichloroethane with a molar ratio of 1:1 was introduced, the space velocity was 300h -1 , and the reaction was carried out at 250°C.
  • the hydrogenation product was analyzed by Agilent 7890A gas chromatography, and the results showed that the conversion rate was 100%, and the selectivity of chlorotrifluoroethylene was 99.38%.
  • Examples 3.24 to 3.46 are the same as those of Example 3.23, except that the catalysts prepared in Examples 3.2 to 3.15 and Comparative Examples 3.1 to 3.9 are used instead of cat3.1 to carry out the hydrodechlorination reaction.
  • Examples 3.47-3.68 are the same as those of Example 3.30, except that Cat3.8 is used as the hydrodechlorination catalyst, and the reaction conditions are changed to carry out the hydrodechlorination reaction.
  • Example 3.69 is a stability experiment performed under the reaction conditions of Example 3.26.

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Abstract

本发明公开了三种核壳结构的加氢脱氯催化剂、其制备方法及其在三氟氯乙烯连续制备中的应用，所述加氢脱氯催化剂包括载体；负载于载体的活性金属，所述活性金属选自钯、铂、铱、镍的至少一种；负载于载体的第二金属，所述第二金属选自铜、锡、银、锌中的一种；所述催化剂呈包裹型核壳结构，核部为活性金属，壳层为第二金属；其中，第一种催化剂的载体为整体式活性炭载体，第二种催化剂的载体为整体式堇青石载体，第三种催化剂的载体为活性炭。本发明的催化剂具有高活性和稳定性，应用于加氢脱氯反应中，能提高反应选择性。

Description

核壳结构的加氢脱氯催化剂、其制备方法及其在三氟氯乙烯连续制备中的应用 技术领域
本发明涉及催化剂领域，特别涉及三种不同载体、不同制备工艺的核壳结构的加氢脱氯催化剂，以及所述核壳结构的加氢脱氯催化剂在气相加氢脱氯反应中的应用，尤其是在三氟三氯乙烷制备三氟氯乙烯中的应用。
背景技术
替代传统化学还原法的催化加氢脱氯技术已经在合成氢氟烃等含氟材料的重要单体反应中引起了人们的广泛关注，被认为是目前最经济绿色、最有应用前景的方法之一。目前，常见的加氢脱氯催化剂主要以钯为主活性组分，镁、钴、铜、铋等为助剂，负载于活性炭、二氧化硅、氟化镁等载体上制备获得，具有良好的加氢脱氯性能。
欧洲专利EP0053657B1公开了将铂系金属负载于碱性氟化镁(如氟化镁钠、氟化镁钾)上制备获得加氢脱氯催化剂，所述催化剂可用于CFC-113制备三氟氯乙烯，CFC-113转化率最高为84％，产品选择性为82～84％。
欧洲专利EP0747337B1和中国专利CN1065261A公开了一种双金属复合碳载催化剂，所述双金属为至少一种VIII族金属和铜复合形成，其中铜占催化剂总质量的12～22％；所述双金属复合催化剂可用于CFC-113的加氢脱氯反应，但反应产物为三氟氯乙烯和三氟乙烯或四氟乙烯，不能选择性获得三氟氯乙烯。
欧洲专利EP0416615A1公开了以Fe、Ni、Cu、Sn、Zn、Cr或其氧化物为催化剂活性组分，二氧化硅、氧化镁、氧化铝、氧化锆、Y型沸石、二氧化硅-氧化铝、碳化硅、硅藻土等作为载体的催化剂，该催化剂可应用于CFC-113加氢脱氯制备三氟氯乙烯，但该催化剂使用不同的活性组分或者载体时选择性差别较大，最高只有80％左右，这使得该催化剂的应用具有一定的局限性。
中国专利CN1351903A公开了一种以贵金属钌或钯或铂与铜为主要活性组分，添加富镧混合稀土或金属镧、碱金属锂作为改质助剂，并以椰壳活性炭为载体的四元催化剂，该催化剂的寿命600小时左右，但在缺少改质助剂的情况下，催化剂的选择性只有70～80％，且此专利提供的方法在活性组分、改质助剂的选择上比较受限。
中国专利CN105457651B公开了一种以Pd和Cu为主催化剂，Mg、Ca、Ba、Co、Mo、 Ni、Sm、Ce中的至少一种为助剂，并负载于活性炭上的加氢脱氯催化剂，所述催化剂可用于CFC-113催化加氢脱氯制备三氟氯乙烯，转化率可达95％，选择性95％，催化剂寿命2000小时。
上述加氢脱氯催化剂均存在催化活性较低、稳定性较差，应用到加氢脱氯反应中时，普遍存在反应选择性低的问题，因此，开发一种活性高、选择性高、稳定性高的新型催化剂显得尤为重要。
发明内容
为了解决上述技术问题，本发明提出了三种高活性和高稳定性的核壳结构的加氢脱氯催化剂，应用于氟氯烷烃的加氢脱氯反应时，能显著提高产物的选择性。
本发明的目的是通过以下技术方案实现的：
在第一方面，本发明提供第一种核壳结构的加氢脱氯催化剂，具体如下：
一种核壳结构的加氢脱氯催化剂，所述催化剂包括：
载体，所述载体为整体式活性炭载体；
负载于载体的活性金属，所述活性金属选自钯、铂、铱、镍的至少一种；
负载于载体的第二金属，所述第二金属选自铜、锡、银、锌中的一种；
所述催化剂呈包裹型结构，核部为活性金属，壳层为第二金属。
一般地，催化剂中的活性金属和第二金属负载于载体上时，各自以离子形式，或者两者形成合金，而本发明催化剂中的活性金属和第二金属主要以单质形式存在，活性金属以单质形式成为核部，第二金属以单质形式成为壳部，活性金属和第二金属形成包裹型双金属粒子，非包覆型粒子以活性金属和第二金属的单金属粒子或合金粒子形式存在。
进一步地，所述活性金属的负载量为0.05～5.0％，第二金属的负载量为0.01～4.0％，且第二金属的负载量不高于活性金属。作为优选，所述活性金属的负载量为0.1～4.0％，第二金属的负载量为0.05～3.0％。
更进一步地，所述活性金属与第二金属的质量比为1～6:1。作为优选，所述活性金属与第二金属的质量比为1.5～4.5:1。
本发明的核壳结构的加氢脱氯催化剂中所述核部活性金属粒子尺寸≤90nm，壳层厚度≤5nm。作为优选，所述核部活性金属粒子尺寸≤60nm，壳层厚度≤3.5nm。
粒子尺寸、壳层厚度及尺寸分布的计算方法：在透射电子显微镜(TEM)照片中随机选 定两到三个区域，进行放大，然后利用Image-Pro Plus软件进行统计分析。表面平均颗粒直径的计算公式为：d s＝Σn id i 3/Σn id i 2。其中，n i表示直径为d i的金属粒子的个数，并且所选取的金属颗粒数目不少于200。
本发明的核壳结构的加氢脱氯催化剂采用整体式活性炭载体，所述整体式活性炭载体的材质选自椰壳、木质或煤质活性炭。相较于常规活性炭载体，整体式活性炭载体能提高流体在催化剂中的流动性，提高催化效率。优选地，所述整体式活性炭载体的比表面积≥900m 2/g，灰份≤3.0wt％，孔密度为10～50孔/cm 2，密度为0.1～0.8g/mL。更为优选地，比表面积≥1100m 2/g，灰份≤2.0wt％，孔密度为15～45孔/cm 2，密度为0.3～0.6g/mL。
常规的催化剂制备办法，并不能获得包裹型催化剂结构。本发明提出了一种核壳结构的加氢脱氯催化剂的制备方法，所述制备方法包括以下步骤：
A1.活性金属负载
将整体式活性炭载体浸渍于活性金属盐溶液中形成浸渍液，在25～85℃下浸渍2～6小时后取出，静置沥干，采用氮气流吹扫；
A2.第二金属负载
将负载有活性金属离子的整体式活性炭载体浸没于乙二醇中，并在乙二醇中通入氢气，搅拌，控制温度为20～95℃，压力为0.1～0.5Mpa，时间为1～10小时，活性金属离子被还原成活性金属单质；
滴入第二金属盐溶液，升温升压反应，反应温度为100～250℃，反应压力为0.1～2.0Mpa，反应时间为3～10小时，反应结束后取出沥干，第二金属离子被还原成第二金属单质包裹于活性金属单质外；
A3.干燥
将负载有活性金属和第二金属的整体式活性炭载体置于氮气气氛下，空速为50～1000h -1，以0.5～2.0℃/min的速率从室温开始升温，至110～150℃后恒温干燥2～5小时，获得催化剂前体；
A4.还原
将催化剂前体置于氢气气氛下，以0.1～2.0℃/min的速率升温至250～450℃，恒温1～5小时，获得所述加氢脱氯催化剂。
作为优选，A1步骤中活性金属的浸渍在搅拌状态下进行，浸渍温度为30～75℃，浸渍 时间为2.5～5小时，且所述浸渍液的总体积与整体式活性炭载体的体积比为2～5:1。
进一步地，A1步骤中取出的负载有活性金属的整体式活性炭载体在20～35℃、空气湿度≤80％的环境下静置10～20小时，沥干，再在流速为0.1～2.0m/s、含0.1～1.0v/v％氧气的氮气流中吹扫0.5～2小时。
作为优选，A2步骤活性金属粒子还原过程中，控制温度50～90℃，压力0.2～0.4Mpa，时间为2～5小时；A2步骤第二金属粒子还原过程中，控制反应温度150～220℃，反应压力0.5～1.5Mpa，反应时间为4～8小时。
为了促进活性金属离子和第二金属离子的还原，更为优选地，所述氢气自反应器的底部经气体分布器通入乙二醇中搅拌反应。所述反应器优选为釜式反应器，底部放置磁子用于搅拌反应，负载有活性金属的整体式活性炭载体置于磁子上方。
上述核壳结构的加氢脱氯催化剂的制备过程中，所述活性金属盐溶液为活性金属硝酸盐溶液或活性金属氯化物溶液。作为优选，所述活性金属盐溶液为金属氯化物溶液，如氯化镍溶液，以及氯离子与贵金属形成的络合物溶液，如[PdCl 4] 2-、[PtCl 4] 2-、[IrCl 4] 2-。
所述第二金属盐溶液为第二金属硝酸盐溶液或第二金属氯化物溶液，溶液浓度为0.5～2.0mol/L。作为优选，所述第二金属盐溶液选自硝酸银、氯化锌、硝酸铜中的至少一种，溶液浓度为0.5～1.5mol/L。
作为优选，A3步骤中空速为100～500h -1，升温速率为0.75～1.75℃/min，至115～145℃后恒温干燥2.5～4.5小时，获得催化剂前体；A4步骤中，空速为100～500h -1，以0.2～1.75℃/min的速率升温至275～400℃，恒温2～4小时，获得所述加氢脱氯催化剂。
根据本发明的方法制备获得的所述加氢脱氯催化剂中，≥85％的第二金属粒子呈包裹型双金属结构，其他呈两金属粒子分散或相互嵌入的状态。更为优选地，本发明制备方法制备获得的所述加氢脱氯催化剂中，≥90％的第二金属粒子呈包裹型双金属结构。
本发明的活性金属具有较强的氢解离性能，在乙二醇浸渍液中充入氢气后，氢气在活性金属粒子上解离成活泼态的氢，诱导第二金属离子在活性金属粒子表面还原，从而形成呈现包裹型结构。初步包裹型结构形成后，会使得氢解离性能的下降，逐渐增加了第二金属进一步地沉积。因此，本发明进一步采用乙二醇作为浸渍液，乙二醇在高温下能表现出还原性，解决第二金属沉积难度逐渐增大的问题，使得第二金属能继续沉积于活性金属外部。在乙二醇浸渍液和氢气的共同作用下，实现了包裹型的核壳结构的加氢脱氯催化剂。
本发明还提供上述任一所述核壳结构的加氢脱氯催化剂的应用，所述催化剂可用于三氟三氯乙烷、1,1,2-三氯-氟乙烷、1,2-二氯四氟乙烷等氟氯烷烃的加氢脱氯反应，也可用于2,3-二氯-1,1,1,4,4,4-六氟-2-丁烯(CFO-1316)等氟氯烯烃的加氢脱氯反应。
本发明还提供一种三氟氯乙烯的连续制备方法，所述连续制备方法包括以下步骤：
采用上述任一所述的核壳结构的加氢脱氯催化剂，以三氟三氯乙烷和氢气为原料经加氢脱氯反应制备获得三氟氯乙烯。
进一步地，所述三氟三氯乙烷与氢气的摩尔比为：1：1～4，优选为1：1～3。
进一步地，所述反应温度为150～300℃，原料空速为10～1300h -1；作为优选，反应温度为160～280℃，原料空速为10～1100h -1。
在第二方面，本发明提供第二种核壳结构的加氢脱氯催化剂，具体如下：
一种整体式堇青石载体加氢脱氯催化剂，所述催化剂包括：
载体，所述载体为整体式堇青石载体；
负载于载体的活性金属，所述活性金属选自钯、铂、铱、镍的至少一种；
负载于载体的第二金属，所述第二金属选自铜、锡、银、锌中的一种；
所述催化剂为呈核壳结构的包裹型双金属粒子，核部为活性金属，壳层为第二金属。
一般地，催化剂中的活性金属和第二金属负载于载体上时，各自以离子形式，或者两者形成合金，而本发明催化剂中的活性金属和第二金属主要以单质形式存在，活性金属以单质形式成为核部，第二金属以单质形式成为壳部，活性金属和第二金属形成双金属粒子，非包覆型粒子以活性金属单金属粒子和第二金属单金属粒子或合金粒子形式存在。
作为优选，所述整体式堇青石载体为氮掺杂炭涂覆的整体式堇青石载体，氮掺杂炭涂层的质量占整体式堇青石载体的0.1～5.0wt％，氮含量占碳涂层质量的0.1～8.0wt％。更为优选地，氮掺杂炭涂层的质量占整体式堇青石载体的0.2～4.0wt％，氮含量占碳涂层质量的0.15～7.0wt％。
进一步地，所述整体式堇青石载体的孔密度为10～50孔/cm 2，比表面积≥900m 2/g。优选地，所述整体式堇青石载体的孔密度为13～48孔/cm 2，比表面积≥1100m 2/g。
本发明的所述氮掺杂炭涂覆的整体式堇青石载体表面的氮掺杂炭涂层的涂覆方法包括以下步骤：
将淀粉、葡萄糖、乙二胺与水按1：1～3：1～3：1～2的质量比配制成水溶液，将整体 式堇青石载体浸没其中，均匀涂覆在整体式堇青石载体表面后取出，在110～150℃下恒温干燥2～3小时，再在氮气气氛中，于400～800℃焙烧3～8小时，即可获得氮掺杂炭涂覆的整体式堇青石载体。
为了更好地涂覆，进一步地，所述整体式堇青石载体经2～5次的重复浸渍涂覆、干燥和焙烧后，获得氮掺杂炭涂覆的堇青石载体。
进一步地，本发明的整体式堇青石载体加氢脱氯催化剂中，所述活性金属的负载量为0.01～4.5％，第二金属的负载量为0.01～5.5，且第二金属的负载量不低于活性金属。作为优选，所述活性金属的负载量为0.05～4.5％，第二金属的负载量为0.05～5.0％。
更进一步地，所述活性金属与第二金属的质量比为1:1～5。作为优选，所述活性金属与第二金属的质量比为1:2～1:5。
本发明的整体式堇青石载体加氢脱氯催化剂中所述核部活性金属粒子尺寸≤100nm，壳层厚度≤5nm。作为优选，所述核部活性金属粒子尺寸≤80nm，壳层厚度≤4.8nm。
粒子尺寸、壳层厚度及尺寸分布的计算方法：在透射电子显微镜(TEM)照片中随机选定两到三个区域，进行放大，然后利用Image-Pro Plus软件进行统计分析。表面平均颗粒直径的计算公式为：d s＝Σn id i 3/Σn id i 2。其中，n i表示直径为d i的金属粒子的个数，并且所选取的金属颗粒数目不少于200。
本发明的整体式堇青石载体加氢脱氯催化剂采用整体式堇青石载体，相较于常规活性炭载体，整体式堇青石载体能提高流体在催化剂中的流动性，提高催化效率。本发明采用氮掺杂炭涂覆的整体式堇青石载体，能有效调控载体的组织结构和表面的化学组成，进一步提升载体表面的催化活性和稳定性。
常规的催化剂制备办法，并不能获得包裹型催化剂结构。本发明提出了一种整体式堇青石载体加氢脱氯催化剂的制备方法，所述制备方法包括以下步骤：
A1.活性金属负载
将氮掺杂炭涂覆的整体式堇青石载体浸渍于活性金属盐溶液形成的浸渍液，在25～85℃下浸渍2～6小时后取出，静置沥干，采用氮气流吹扫；
A2.第二金属负载
将负载有活性金属的整体式堇青石载体浸没于乙二醇中，并在乙二醇中通入氢气，搅拌，控制温度为20～95℃，压力为0.1～0.2Mpa，时间为1～10小时，活性金属离子被还原成活 性金属单质；
滴入第二金属盐溶液，升温升压反应，反应温度为150～350℃，反应压力为0.5～4.0Mpa，反应时间为3～10小时，反应结束后取出沥干，第二金属离子被还原成第二金属单质包裹在活性金属单质外；
A3.干燥
将负载有活性金属和第二金属的整体式堇青石载体置于氮气气氛下，以0.5～2.0℃/min的速率从室温开始升温，至110～150℃后恒温干燥2～5小时，获得催化剂前体；
A4.还原
将催化剂前体置于氢气气氛下，空速为不低于100h -1，以0.1～2.0℃/min的速率升温至250～450℃，恒温1～5小时，获得所述加氢脱氯催化剂。
作为优选，A1步骤中活性金属的浸渍在搅拌状态下进行，浸渍温度为35～70℃，浸渍时间为3～5小时，且所述浸渍液的总体积与整体式堇青石载体的体积比为2～5:1。
进一步地，A1步骤中取出的负载有活性金属的整体式堇青石载体在20～35℃、空气湿度≤80％的环境下静置10～20小时，沥干，再在流速为0.1～2.0m/s、含0.1～1.0v/v％氧气的氮气流中吹扫0.5～2小时。
作为优选，A2步骤中活性金属还原时，控制温度为60～90℃，压力为0.1～0.15Mpa，时间为2～5小时；A2步骤中第二金属离子负载时，反应温度250～350℃，反应压力0.5～3.5MPa，反应时间5～7小时。
为了促进活性金属离子和第二金属离子的还原，更为优选地，所述氢气自反应器的底部经气体分布器通入乙二醇中搅拌反应。所述反应器优选为釜式反应器，底部放置磁子用于搅拌反应，负载有活性金属离子的整体式堇青石载体置于磁子上方。
上述整体式堇青石载体加氢脱氯催化剂的制备过程中，所述活性金属盐溶液为活性金属硝酸盐溶液或活性金属氯化物溶液。作为优选，所述活性金属盐溶液为金属氯化物溶液，如氯化镍溶液，以及氯离子与贵金属形成的络合物溶液，如[PdCl 4] 2-、[PtCl 4] 2-、[IrCl 4] 2-。
所述第二金属盐溶液为第二金属硝酸盐溶液或第二金属氯化物溶液，溶液浓度为0.5～2.0mol/L。作为优选，所述第二金属盐溶液选自硝酸银、氯化锌、硝酸铜中的至少一种，溶液浓度为1.0～1.5mol/L。
作为优选，A3步骤中升温速率为1.0～1.5℃/min，至120～140℃后恒温干燥2.5～4.8小 时，获得催化剂前体；A4步骤中，空速为100～1000h -1，以0.5～1.5℃/min的速率升温至300～400℃，恒温2～3.8小时，获得所述加氢脱氯催化剂。
根据本发明的方法制备获得的所述加氢脱氯催化剂中，≥90％的活性金属粒子呈包裹型双金属结构，其他呈两金属粒子分散或相互嵌入的状态。更为优选地，本发明制备方法制备获得的所述加氢脱氯催化剂中，≥95％的活性金属粒子呈包裹型双金属结构。
本发明的活性金属具有较强的氢解离性能，在乙二醇浸渍液中充入氢气后，氢气在活性金属粒子上解离成活泼态的氢，诱导第二金属离子在活性金属粒子表面还原，从而形成呈现包裹型结构。初步包裹型结构形成后，会使得氢解离性能的下降，逐渐增加了第二金属进一步地沉积。因此，本发明进一步采用乙二醇作为浸渍液，乙二醇在高温下能表现出还原性，解决第二金属沉积难度逐渐增大的问题，使得第二金属能继续沉积于活性金属外部。在乙二醇浸渍液和氢气的共同作用下，实现了包裹型的整体式堇青石载体加氢脱氯催化剂。
本发明还提供上述任一所述整体式堇青石载体加氢脱氯催化剂的应用，所述催化剂可用于三氟三氯乙烷、1,1,2-三氯-氟乙烷、1,2-二氯四氟乙烷等氟氯烷烃的加氢脱氯反应，也可用于2,3-二氯-1,1,1,4,4,4-六氟-2-丁烯(CFO-1316)等氟氯烯烃的加氢脱氯反应。
本发明还提供一种三氟氯乙烯的连续制备方法，所述制备方法包括以下步骤：
采用上述任一所述的整体式堇青石载体加氢脱氯催化剂，以三氟三氯乙烷和氢气为原料经加氢脱氯反应制备获得三氟氯乙烯。
进一步地，所述三氟三氯乙烷与氢气的摩尔比为1：1～4，优选为1:1～3.5。
进一步地，所述反应温度为150～300℃，原料空速为10～1500h -1；作为优选，反应温度为170～280℃，原料空速为10～1200h -1。
在第三方面，本发明提供第三种核壳结构的加氢脱氯催化剂，具体如下：
一种高选择性加氢脱氯催化剂，所述催化剂包括：
载体，所述载体为活性炭；
负载于载体的活性金属，所述活性金属选自钯、铂、铱、镍的至少一种；
负载于载体的第二金属，所述第二金属选自铜、锡、银、锌中的一种；
所述催化剂主要为呈核壳结构的包裹型双金属粒子，核部为活性金属，壳层为第二金属，活性金属和第二金属形成包裹型双金属粒子，非包覆型粒子以活性金属单金属粒子和第二金属的单金属粒子或合金粒子形式存在。
一般地，催化剂中的活性金属和第二金属负载于载体上时，各自以离子形式，或者两者形成合金，而本发明催化剂中的活性金属和第二金属均以单质形式存在，活性金属以单质形式成为核部，第二金属以单质形式成为壳部，活性金属和第二金属形成双金属粒子。
进一步地，所述活性金属的负载量为0.05～5.0％，第二金属的负载量为0.1～8.0％，且第二金属的负载量不低于活性金属。作为优选，所述活性金属的负载量为0.1～4.5％，第二金属的负载量为0.1～5.0％。
更进一步地，所述活性金属与第二金属的质量比为1：1～6。作为优选，所述活性金属与第二金属的质量比为1：1～5。
本发明的高选择性加氢脱氯催化剂中所述核部活性金属粒子尺寸≤65nm，壳层厚度≤10nm。作为优选，所述核部活性金属粒子尺寸≤55nm，壳层厚度≤8.0nm。
粒子尺寸、壳层厚度及尺寸分布的计算方法：在透射电子显微镜(TEM)照片中随机选定两到三个区域，进行放大，然后利用Image-Pro Plus软件进行统计分析。表面平均颗粒直径的计算公式为：d s＝Σn id i 3/Σn id i 2。其中，n i表示直径为d i的金属粒子的个数，并且所选取的金属颗粒数目不少于200。
本发明的高选择性加氢脱氯催化剂的载体为颗粒状活性炭或柱状活性炭，材质选自椰壳、木制或煤质活性炭。作为优选，所述活性炭载体的比表面积≥1000m 2/g，灰份≤3.0wt％。更为优选地，活性炭载体的比表面积≥1100m 2/g，灰份≤2.8wt％。
常规的催化剂制备办法，并不能获得包裹型催化剂结构。本发明提出了一种核壳结构的高选择性加氢脱氯催化剂的制备方法，所述制备方法包括以下步骤：
A1.活性金属粒子制备
按负载量配置活性金属盐的浸渍液，在25～95℃，超声下浸渍0.5～10小时后离心分离，获得活性金属粒子；所述浸渍液为乙二醇水溶液、甲醛水溶液或葡萄糖水溶液中的至少一种；
A2.第二金属粒子包裹
将活性金属粒子、按负载量配置的第二金属盐溶液加入还原试剂水溶液中，搅拌下通入氢气，氢气压力为0.1～2.0MPa，控制温度100～300℃，1～10小时后离心分离，获得包裹型双金属粒子；
A3.双金属粒子负载
将所述包裹型双金属粒子置于去离子水中，搅拌状态下加入活性炭载体，浸渍、过滤、洗涤，获得活性炭负载的双金属粒子；浸渍温度为20～80℃，浸渍时间为1～10小时；
A4.干燥
将活性炭负载的双金属粒子置于氮气气氛下，以0.5～2.0℃/min的速率从室温开始升温，至110～150℃后恒温干燥2～5小时，获得催化剂前体；
A5.还原
将催化剂前体置于氢气气氛下，以0.1～2.0℃/min的速率升温至250～450℃，恒温1～5小时，获得所述加氢脱氯催化剂。
所述A1步骤在超声下进行浸渍、还原，使得体系均匀分散，避免活性金属发生团聚。所述超声频率为30～50kHz，功率为300～1000w。
作为一种优选的实施方式，所述活性金属盐为活性金属硝酸盐或活性金属氯化物，更优选为活性金属氯化物，如氯化镍，以及氯离子与贵金属形成的络合物，如[PdCl 4] 2-、[PtCl 4] 2-、[IrCl 4] 2-。作为浸渍液的乙二醇水溶液、甲醛水溶液或葡萄糖水溶液中的一种或多种的质量含量为1～20wt％，更优选为2～18％。浸渍温度为35～80℃，浸渍时间为2～8h。浸渍结束后采用离心分离，并用去离子水将获得的活性金属粒子洗涤至中性。
为了促进第二金属离子的包裹与还原，所述A2步骤中，在搅拌状态下向还原试剂中通入氢气，优选地，所述氢气自反应器的底部经气体分布器通入；所述反应器优选为釜式反应器，底部放置磁子用于搅拌，搅拌转速优选为1000～3000r/min。所述第二金属盐溶液为第二金属硝酸盐溶液或第二金属氯化物溶液，溶液浓度为0.1～2.0mol/L；所述还原试剂为乙二醇、硼氢化钠或水合肼中的至少一种，其溶液为质量含量为5～50wt％的水溶液，且所述还原试剂与第二金属的质量比为1:20～100。更为优选地，所述还原试剂水溶液为质量含量为10～40wt％的乙二醇、硼氢化钠或水合肼水溶液，还原试剂与第二金属的质量比为1:30～90。
作为一种优选的实施方式，在A2步骤中，优选氢气压力为0.2～1.8MPa，控制温度150～250℃，反应2～5小时。反应结束后离心分离，将获得的包裹型双金属粒子用去离子水洗涤至中性。
为了实现双金属粒子在载体上的均匀负载，在A3步骤中，将包裹型双金属粒子先置于去离子水中，超声5～20分钟、搅拌1～3小时，使得双金属粒子均匀分散，再在搅拌状态下加入活性炭载体，搅拌转速为1000～3000r/min。活性炭载体的体积与浸渍液的总体积的比为 1:1～5，优选体积比为1:2～4.5。
双金属粒子在活性炭载体上均匀负载后，经过滤并洗涤至中性，还需要进一步干燥与还原。作为优选，在所述A4干燥步骤中的升温速率为0.8～1.8℃/min，至115～140℃后恒温干燥2.5～4.5小时，空速大于100h -1，获得催化剂前体；A5步骤中，以0.2～1.9℃/min的速率升温至280～430℃，恒温1～4小时，空速大于100h -1，获得所述加氢脱氯催化剂。
根据本发明的方法制备获得的所述高选择性加氢脱氯催化剂中，≥80％的活性金属粒子呈包裹型双金属结构，其他呈两金属粒子分散或相互嵌入的状态。更为优选地，本发明制备方法制备获得的所述加氢脱氯催化剂中，≥85％的活性金属粒子呈包裹型双金属结构。
本发明的活性金属具有较强的氢解离性能，氢气会在活性金属粒子上解离成活泼态的氢，诱导第二金属离子在活性金属粒子表面还原，从而形成呈现包裹型结构。初步包裹型结构形成后，会使得氢解离性能下降，逐渐增加了第二金属进一步沉积的难度。因此，本发明进一步采用乙二醇、硼氢化钠或水合肼的水溶液作为还原试剂，所述还原试剂在高温下能表现出还原性，解决第二金属沉积难度逐渐增大的问题，使得第二金属能继续沉积于活性金属外部。本发明在还原试剂和氢气的共同作用下，实现了包裹型的高选择性加氢脱氯催化剂的制备。
本发明还提供上述任一所述高选择性加氢脱氯催化剂的应用，所述催化剂可用于三氟三氯乙烷、1,1,2-三氯-氟乙烷、1,2-二氯四氟乙烷等氟氯烷烃的加氢脱氯反应，也可用于2,3-二氯-1,1,1,4,4,4-六氟-2-丁烯(CFO-1316)等氟氯烯烃的加氢脱氯反应。
本发明还提供一种三氟氯乙烯的连续制备方法，所述制备方法包括以下步骤：
采用上述任一所述的高选择性加氢脱氯催化剂，以三氟三氯乙烷和氢气为原料经加氢脱氯反应制备获得三氟氯乙烯。
进一步地，所述三氟三氯乙烷与氢气的摩尔比为1：1～4，优选为1：1～3.5。
进一步地，所述反应温度为150～300℃，原料空速为10～1200h -1；作为优选，反应温度为180～290℃，原料空速为10～900h -1。
与现有技术相比，本发明具有的有益效果包括：
1.本发明的三种催化剂均为核壳结构，核部为活性金属，壳部为第二金属，形成包裹型双金属结构，电子在两种金属结构之间发生偏移，调变了氢解离性能和碳氯键(C-Cl)活化性能，使得催化剂具有高活性和高稳定性。
2.本发明的三种催化剂分别用于加氢脱氯反应时，均能提高产物的选择性，尤其是用于 三氟三氯乙烷的加氢脱氯反应时，三氟氯乙烯的选择性≥99％，最高可达99.8％以上。
3.本发明的第一种催化剂采用整体式活性炭载体，降低了催化剂床层压降，提高了流体在催化剂中的流动性，进而提高了催化效率和催化反应稳定运行时间，解决了颗粒状催化剂粉末易堵塞床层的问题。
4.本发明的第二种催化剂采用整体式堇青石载体，降低了催化剂层压，提高了流体在催化剂中的流动性，进而提高了催化效率；且所述整体式堇青石载体为氮掺杂炭涂覆的整体式堇青石载体，能有效调控载体的组织结构和表面的化学组成，能进一步提升载体表面的催化活性和稳定性。
附图说明
图1为本发明实施例1.1制备获得的核壳结构的加氢脱氯催化剂的TEM表征图；
图2为本发明实施例2.1制备获得的整体式堇青石载体加氢脱氯催化剂的TEM表征图；
图3为本发明实施例3.1制备获得的高选择性加氢脱氯催化剂的TEM表征图。
具体实施方式
下面结合具体实施例来对本发明进行进一步说明，但并不将本发明局限于这些具体实施方式。本领域技术人员应该认识到，本发明涵盖了权利要求书范围内所可能包括的所有备选方案、改进方案和等效方案。
(第一方面)、本发明实施例第一种核壳结构的加氢脱氯催化剂的制备及应用。
实施例1.1
加氢脱氯催化剂的制备：
S1.活性金属负载：将整体式活性炭载体(煤质，1000m 2/g，灰份2.0wt％，孔密度30孔/cm 2，密度0.5g/mL)用去离子水冲洗干净后，浸没于氯钯酸水溶液中，钯含量为整体式活性炭载体的1.0％，浸渍液总体积与整体式活性炭载体的体积比为2:1。开启搅拌，升温至50℃，浸渍3小时后取出；在30℃、空气湿度70％下静置15小时沥干，然后用流速为0.5m/s的氮气流(含0.1v/v氧气)吹扫1小时。
S2.第二金属负载：1)活性金属还原：将氮气流吹扫过的负载有活性金属的整体式活性炭载体置于高压反应釜内，浸没于乙二醇溶液中，釜底加磁子用于搅拌(转数1500r/min)，在乙二醇溶液中持续通入氢气，升温至80℃保温反应5小时，反应压力为0.1MPa；2)第二金属负载：升高温度至180℃，增加压力至1.0MPa，并按负载量为1.0％，移取1mol/L的氯 化铜溶液，通过恒压漏斗滴入高压釜内，继续恒温反应5小时。
S3.干燥：将负载有活性金属和第二金属的整体式活性炭载体置于管式炉内，在氮气气氛下(空速为300h -1)以0.5℃/min的速率从室温升至120℃，恒温干燥5小时获得催化剂前体。
S4.还原：将获得的催化剂前体在氢气气氛下(空速为300h -1)，以0.1℃/min的速率从室温升温至350℃，恒温5小时，获得所述加氢脱氯催化剂，记为cat1.1。
图1给出了本实施制备获得的加氢脱氯催化剂的TEM表征图，从图中看出，本实施例的加氢脱氯催化剂形成包裹型结构，核为钯，壳为铜。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，92％的第二金属粒子呈包裹型双金属结构。
实施例1.2
本实施例的操作同实施例1.1，区别仅在于：整体式活性炭载体的材质采用木质代替煤质，制备获得加氢脱氯催化剂，记为cat1.2。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，91％的第二金属粒子呈包裹型双金属结构。
实施例1.3
本实施例的操作同实施例1.1，区别仅在于：整体式活性炭载体的比表面积1200m 2/g，灰份1.8wt％，孔密度20孔/cm 2，密度0.6g/mL。制备获得加氢脱氯催化剂，记为cat1.3。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，93％的第二金属粒子呈包裹型双金属结构。
实施例1.4
本实施例的操作同实施例1.1，区别仅在于：活性金属钯的负载量为1.5％，第二金属铜的负载量为1.0％。制备获得加氢脱氯催化剂，记为cat1.4。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，90％的第二金属粒子呈包裹型双金属结构。
实施例1.5
本实施例的操作同实施例1.1，区别仅在于：活性金属钯的负载量为2.5％，第二金属铜的负载量为0.05％。制备获得加氢脱氯催化剂，记为cat1.5。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，95％的第二金属粒子呈包裹型双金属结构。
实施例1.6
本实施例的操作同实施例1.1，区别仅在于：活性金属采用铂，第二金属采用锌，活性金属和第二金属的负载量不变。制备获得加氢脱氯催化剂，记为cat1.6。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，94％的第二金属粒子呈包裹型双金属结构。
实施例1.7
本实施例的操作同实施例1.1，区别仅在于：活性金属采用镍，第二金属采用锌，活性金属和第二金属的负载量不变。制备获得加氢脱氯催化剂，记为cat1.7。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，94％的第二金属粒子呈包裹型双金属结构。
实施例1.8
本实施例的操作同实施例1.1，区别仅在于：活性金属溶液采用硝酸钯代替氯钯酸，第二金属溶液采用氯化锌代替氯化铜，活性金属和第二金属的负载量不变。制备获得加氢脱氯催化剂，记为cat1.8。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，88％的第二金属粒子呈包裹型双金属结构。
实施例1.9
本实施例的操作同实施例1.1，区别仅在于：活性金属溶液为氯钯酸，第二金属溶液采用硝酸锌代替氯化铜，活性金属和第二金属的负载量不变。制备获得加氢脱氯催化剂，记为cat1.9。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，85％的第二金属粒子呈包裹型双金属结构。
实施例1.10
本实施例的操作同实施例1.1，区别仅在于：S1步骤中，浸渍液总体积与整体式活性炭载体的体积比改为5:1。制备获得加氢脱氯催化剂，记为cat1.10。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，93％的第二金属粒子呈包裹型双金 属结构。
实施例1.11
本实施例的操作同实施例1.1，区别仅在于：S1步骤中，浸渍液总体积与整体式活性炭载体的体积比为1:1。制备获得加氢脱氯催化剂，记为cat1.11。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，94％的第二金属粒子呈包裹型双金属结构。
实施例1.12
本实施例的操作同实施例1.1，区别仅在于：S1步骤中，浸渍温度改为75℃。制备获得加氢脱氯催化剂，记为cat1.12。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，87％的第二金属粒子呈包裹型双金属结构。
实施例1.13
本实施例的操作同实施例1.1，区别仅在于：S1步骤中，浸渍时间改为5小时。制备获得加氢脱氯催化剂，记为cat1.13。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，88％的第二金属粒子呈包裹型双金属结构。
实施例1.14
本实施例的操作同实施例1.1，区别仅在于：S1步骤中，取出的负载有活性金属的整体式活性炭载体在20℃环境下静置。制备获得加氢脱氯催化剂，记为cat1.14。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，86％的第二金属粒子呈包裹型双金属结构。
实施例1.15
本实施例的操作同实施例1.1，区别仅在于：S1步骤中，取出的负载有活性金属的整体式活性炭载体在空气湿度50％的环境下静置。制备获得加氢脱氯催化剂，记为cat1.15。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，94％的第二金属粒子呈包裹型双金属结构。
实施例1.16
本实施例的操作同实施例1.1，区别仅在于：S1步骤中，取出的负载有活性金属的整体 式活性炭载体静置20小时。制备获得加氢脱氯催化剂，记为cat1.16。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，96％的第二金属粒子呈包裹型双金属结构。
实施例1.17
本实施例的操作同实施例1.1，区别仅在于：S1步骤中，取出的负载有活性金属的整体式活性炭载体沥干后在2.0m/s氮气流中吹扫。制备获得加氢脱氯催化剂，记为cat1.17。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，93％的第二金属粒子呈包裹型双金属结构。
实施例1.18
本实施例的操作同实施例1.1，区别仅在于：S1步骤中，取出的负载有活性金属的整体式活性炭载体沥干后氮气流中含氧1.0v/v％。制备获得加氢脱氯催化剂，记为cat1.18。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，91％的第二金属粒子呈包裹型双金属结构。
实施例1.19
本实施例的操作同实施例1.1，区别仅在于：S1步骤中，取出的负载有活性金属的整体式活性炭载体沥干后氮气流中吹扫2小时。制备获得加氢脱氯催化剂，记为cat1.19。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，90％的第二金属粒子呈包裹型双金属结构。
实施例1.20
本实施例的操作同实施例1.1，区别仅在于：S2步骤中活性金属粒子还原温度为50℃。制备获得加氢脱氯催化剂，记为cat1.20。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，89％的第二金属粒子呈包裹型双金属结构。
实施例1.21
本实施例的操作同实施例1.1，区别仅在于：S2步骤中活性金属粒子还原压力为0.5MPa。制备获得加氢脱氯催化剂，记为cat1.21。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，87％的第二金属粒子呈包裹型双金属结构。
实施例1.22
本实施例的操作同实施例1.1，区别仅在于：S2步骤中活性金属李老师子还原时间由5小时改为2小时。制备获得加氢脱氯催化剂，记为cat1.22。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，90％的第二金属粒子呈包裹型双金属结构。
实施例1.23
本实施例的操作同实施例1.1，区别仅在于：S2步骤中第二金属粒子还原温度升高为220℃。制备获得加氢脱氯催化剂，记为cat1.23。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，93％的第二金属粒子呈包裹型双金属结构。
实施例1.24
本实施例的操作同实施例1.1，区别仅在于：S2步骤中第二金属粒子还原压力增加至1.5Mpa。制备获得加氢脱氯催化剂，记为cat1.24。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，86％的第二金属粒子呈包裹型双金属结构。
实施例1.25
本实施例的操作同实施例1.1，区别仅在于：S2步骤中第二金属粒子还原时间增加至8小时。制备获得加氢脱氯催化剂，记为cat1.25。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，93％的第二金属粒子呈包裹型双金属结构。
实施例1.26
本实施例的操作同实施例1.1，区别仅在于：S3步骤中升温速率提高至1.75℃/min。制备获得加氢脱氯催化剂，记为cat1.26。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，95％的第二金属粒子呈包裹型双金属结构。
实施例1.27
本实施例的操作同实施例1.1，区别仅在于：S3步骤中恒温温度提高至145℃。制备获得加氢脱氯催化剂，记为cat1.27。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，89％的第二金属粒子呈包裹型双金属结构。
实施例1.28
本实施例的操作同实施例1.1，区别仅在于：S3步骤中恒温时间降低为2.5小时。制备获得加氢脱氯催化剂，记为cat1.28。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，91％的第二金属粒子呈包裹型双金属结构。
实施例1.29
本实施例的操作同实施例1.1，区别仅在于：S4步骤中升温速率提高至1.75℃/min。制备获得加氢脱氯催化剂，记为cat1.29。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，93％的第二金属粒子呈包裹型双金属结构。
实施例1.30
本实施例的操作同实施例1.1，区别仅在于：S4步骤中恒温温度降低为300℃。制备获得加氢脱氯催化剂，记为cat1.30。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，89％的第二金属粒子呈包裹型双金属结构。
实施例1.31
本实施例的操作同实施例1.1，区别仅在于：S4步骤中恒温时间降低为4小时。制备获得加氢脱氯催化剂，记为cat1.31。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，91％的第二金属粒子呈包裹型双金属结构。
对比例1.1
本对比例的操作同实施例1.1，区别仅在于：采用柱状活性炭代替整体式活性炭载体，制备获得的催化剂记为B1.1。
经TEM表征，制备获得的催化剂中，45％的第二金属粒子呈包裹型双金属结构。
对比例1.2
本对比例的操作同实施例1.1，区别仅在于：S1步骤中从浸渍液中取出的整体式活性炭 载体直接置于氮气流中吹扫，省略静置沥干过程。制备获得的催化剂记为B1.2。
经TEM表征，制备获得的催化剂中，48％的第二金属粒子呈包裹型双金属结构。
对比例1.3
本对比例的操作同实施例1.1，区别仅在于：S1步骤中从浸渍液中取出的整体式活性炭载体在静置沥干后，未经氮气流吹扫，直接进行第二金属负载。制备获得的催化剂记为B1.3。
经TEM表征，制备获得的催化剂中，52％的第二金属粒子呈包裹型双金属结构。
对比例1.4
本对比例的操作同实施例1.1，区别仅在于：S2步骤中，在乙二醇溶液中通入氢气后，直接升温至180℃，升压至1.0MPa进行第二金属负载，未进行活性金属还原步骤。制备获得的催化剂记为B1.4。
经TEM表征，制备获得的催化剂中，55％的第二金属粒子呈包裹型双金属结构。
对比例1.5
本对比例的操作同实施例1.1，区别仅在于：S2步骤中，仅在活性金属还原步骤通入氢气，第二金属浸渍时停止通入氢气。制备获得的催化剂记为B1.5。
经TEM表征，制备获得的催化剂中，54％的第二金属粒子呈包裹型双金属结构。
对比例1.6
本对比例的操作同实施例1.1，区别仅在于：S2步骤中第二金属负载时，改为常温常压反应，而非180℃、1.0MPa的反应条件。制备获得的催化剂记为B1.6。经TEM表征，制备获得的催化剂中，51％的第二金属粒子呈包裹型双金属结构。
对比例1.7
本对比例的操作同实施例1.1，区别仅在于：S2步骤中采用甲醇代替乙二醇溶液，制备获得的催化剂记为B1.7。
经TEM表征，制备获得的催化剂中，32％的第二金属粒子呈包裹型双金属结构。
对比例1.8
本对比例的操作同实施例1.1，区别仅在于：本对比例制备过程中不采用载体，具体过程包括：将氯钯酸溶液加入乙二醇溶液中，并在搅拌状态下持续通入氢气；加入氯化铜溶液混合，升温升压反应；在氮气气氛下恒温干燥；在氢气气氛下还原。制备获得的催化剂记为B1.8，得到的金属粒子尺寸为100～800nm，大小分布不均。
经TEM表征，制备获得的催化剂中，36％的第二金属粒子呈包裹型双金属结构。
对比例1.9
将整体式活性炭载体(煤质，1000m 2/g，灰份2.0wt％，孔密度30孔/cm 2，密度0.5g/mL)用去离子水冲洗干净后，浸没于氯钯酸和氯化铜水溶液中，钯和铜的含量为整体式活性炭载体的1.0％和1.0％，浸渍液总体积与整体式活性炭载体的体积比为2:1。开启搅拌，升温至50℃，浸渍3小时后取出。在30℃、空气湿度70％下静置15小时沥干，然后用流速为0.5m/s的氮气流(含0.1v/v氧气)吹扫1小时。
干燥与还原步骤的操作同实施例1.1中的干燥与还原步骤。
制备获得的催化剂记为B1.9，经TEM表征，钯铜双金属没有形成包裹型核壳结构，为双金属合金状态。
实施例1.32
本实施例为加氢脱氯催化剂在三氟三氯乙烷加氢脱氯制备三氟氯乙烯反应中的应用，具体步骤如下：
将5g实施例1.1制备获得的Cat1.1装入固定床反应器中，反应器内径10mm。升温至250℃，通入摩尔比为1:1的氢气与三氟三氯乙烷组成的混合气，空速为300h -1，250℃下反应。
加氢产物用Agilent 7890A气相色谱分析，结果显示转化率100％，三氟氯乙烯选择性99.58％。
实施例1.33-1.71
实施例1.33-1.71的操作同实施例1.32，区别仅在于：采用cat1.2～cat1.31、催化剂B1.1～B1.9代替cat1.1进行加氢脱氯反应。
加氢产物用Agilent 7890A气相色谱分析，分析结果如下表1所示：
表1不同催化剂下三氟三氯乙烷加氢脱氯反应结果
Figure PCTCN2021117089-appb-000001
Figure PCTCN2021117089-appb-000002
实施例1.72-1.93
实施例1.72-1.93的操作步骤同实施例1.32，区别仅在于：采用Cat1.6作为加氢脱氯催化剂，改变反应条件进行加氢脱氯反应。
加氢产物用Agilent 7890A气相色谱分析，分析结果如下表2所示：
表2不同反应条件下三氟三氯乙烷加氢脱氯反应结果
Figure PCTCN2021117089-appb-000003
实施例1.94
实施例1.94是在实施例1.80的反应条件下进行的稳定性实验。
加氢产物用Agilent 7890A气相色谱分析，分析结果如下表3所示：
表3三氟三氯乙烷加氢脱氯反应稳定性结果
时间/天 转化率/％ 选择性/％
1 100 99.68
2 100 99.67
3 100 99.59
4 100 99.78
5 100 99.56
6 100 99.28
7 100 99.67
8 100 99.49
9 100 99.54
10 100 99.58
11 100 99.68
12 100 99.57
13 100 99.68
14 100 99.69
15 100 99.64
16 100 99.90
17 100 99.61
18 100 99.57
19 100 99.53
20 100 99.56
21 100 99.63
22 100 99.72
23 100 99.71
24 100 99.72
25 100 99.74
26 100 99.72
27 100 99.78
28 100 99.46
29 100 99.28
30 100 99.68
40 100 99.61
50 100 99.67
60 100 99.82
70 100 99.46
80 100 99.47
90 100 99.56
100 100 99.61
120 100 99.62
150 100 99.35
180 100 99.67
(第二方面)、本发明实施例第二种核壳结构的加氢脱氯催化剂的制备及应用。
制备例
氮掺杂炭涂覆的整体式堇青石载体的制备：
将淀粉、葡萄糖、乙二胺与水按1：2：2：2的质量比配制成水溶液，将整体式堇青石载体浸没其中，均匀涂覆在整体式堇青石载体表面后取出，110℃下干燥3小时后置于氮气气氛中，于400℃焙烧5小时。在相同条件下，继续重复浸渍涂覆、干燥、焙烧。经三次涂覆、 干燥和焙烧后获得氮掺杂炭涂覆的整体式堇青石载体，所述氮掺杂炭涂覆的整体式堇青石载体的比表面积为1270m 2/g，炭涂层含量4.0wt％，其中氮含量5.0wt％。
改变氮掺杂炭涂层的涂覆条件，获得不同比表面积、碳含量和氮含量的整体式堇青石载体，具体如下表4所示：
表4氮掺杂炭涂覆的整体式堇青石载体
Figure PCTCN2021117089-appb-000004
实施例2.1
加氢脱氯催化剂的制备：
S1.活性金属负载：将上述制备获得的氮掺杂炭涂覆的整体式堇青石载体1用去离子水冲洗干净后，浸没于氯钯酸水溶液中，钯含量为整体式堇青石载体的0.08％，浸渍液总体积与整体式堇青石载体的体积比为2:1。开启搅拌，升温至50℃，浸渍3小时后取出；在30℃、空气湿度70％下静置15小时沥干，然后用流速为0.5m/s的氮气流(含0.1v/v氧气)吹扫1小时。
S2.第二金属负载：1)活性金属离子还原：将氮气流吹扫过的负载有活性金属的整体式 堇青石载体置于高压反应釜内，浸没于乙二醇溶液中，釜底加磁子用于搅拌(转数1500r/min)，在乙二醇溶液中持续通入氢气，升温至80℃保温5小时，控制压力为0.1MPa；2)第二金属负载：升高温度至250℃，增加压力至1.0MPa，并按0.08％的负载量移取1mol/L的氯化铜溶液，通过恒压漏斗滴入高压釜内，继续恒温反应5小时。
S3.干燥：将负载有活性金属和第二金属的整体式堇青石载体置于管式炉内，在氮气气氛下以0.5℃/min的速率从室温升至120℃，恒温干燥5小时获得催化剂前体。
S4.还原：将获得的催化剂前体在氢气气氛下(空速为200h -1)，以0.1℃/min的速率从室温升温至350℃，恒温5小时，获得所述加氢脱氯催化剂，记为cat2.1。
图1给出了本实施制备获得的加氢脱氯催化剂的TEM表征图，从图中看出，本实施例的加氢脱氯催化剂形成包裹型结构，核为钯，壳为铜。
经TEM表征，所述cat2.1中91％活性金属粒子呈包裹型双金属结构。
实施例2.2
本实施例的操作同实施例2.1，区别仅在于：采用载体3代替载体1进行加氢脱氯催化剂的制备，活性金属负载量为0.8％，第二金属负载量降低至1.5％，制备获得的催化剂记为cat2.2。
经TEM表征，所述cat2.2中93％的活性金属粒子呈包裹型双金属结构。
实施例2.3
本实施例的操作同实施例2.1，区别仅在于：采用载体8代替载体1进行加氢脱氯催化剂的制备，活性金属负载量为0.3％，第二金属负载量降低至1.5％，制备获得的催化剂记为cat2.3。
经TEM表征，所述cat2.3中90％的活性金属粒子呈包裹型双金属结构。
实施例2.4
本实施例的操作同实施例2.1，区别仅在于：采用载体12代替载体1进行加氢脱氯催化剂的制备，活性金属为铂，第二金属改为锌，制备获得的催化剂记为cat2.4。
经TEM表征，所述cat2.4中97％的活性金属粒子呈包裹型双金属结构。
实施例2.5
本实施例的操作同实施例2.1，区别仅在于：采用载体18代替载体1进行加氢脱氯催化剂的制备，活性金属改为镍，第二金属改为锌，制备获得的催化剂记为cat2.5。
经TEM表征，所述cat2.5中96％的活性金属粒子呈包裹型双金属结构。
实施例2.6
本实施例的操作同实施例2.1，区别仅在于：采用载体2代替载体1进行加氢脱氯催化剂的制备，活性金属钯的负载量为1％，第二金属铜的负载量为1.5％。制备获得加氢脱氯催化剂，记为cat2.6。
经TEM表征，所述cat2.6中95％的活性金属粒子呈包裹型双金属结构。
实施例2.7
本实施例的操作同实施例2.1，区别仅在于：采用载体7代替载体1进行加氢脱氯催化剂的制备，活性金属溶液(活性金属前驱体)采用硝酸钯，第二金属溶液采用氯化锌，制备获得的催化剂记为cat2.7。
经TEM表征，所述cat2.7中93％的活性金属粒子呈包裹型双金属结构。
实施例2.8
本实施例的操作同实施例2.1，区别仅在于：采用载体4代替载体1进行加氢脱氯催化剂的制备，活性金属溶液(活性金属前驱体)采用硝酸钯，第二金属溶液采用硝酸锌，制备获得的催化剂记为cat2.8。
经TEM表征，所述cat2.8中96％的活性金属粒子呈包裹型双金属结构。
实施例2.9
本实施例的操作同实施例2.1，区别仅在于：采用载体9代替载体1进行加氢脱氯催化剂的制备，S1步骤中，浸渍温度为升高为60℃，制备获得的催化剂记为cat2.9。
经TEM表征，所述cat2.9中92％的活性金属粒子呈包裹型双金属结构。
实施例2.10
本实施例的操作同实施例2.1，区别仅在于：采用载体10代替载体1进行加氢脱氯催化剂的制备，S1步骤中，浸渍时间增加至6小时，制备获得的催化剂记为cat2.10。
经TEM表征，所述cat2.10中95％的活性金属粒子呈包裹型双金属结构。
实施例2.11
本实施例的操作同实施例2.1，区别仅在于：采用载体11代替载体1进行加氢脱氯催化剂的制备，S2步骤中，活性金属离子还原压力为0.2MPa，制备获得的催化剂记为cat2.11。
经TEM表征，所述cat2.11中94％的活性金属粒子呈包裹型双金属结构。
实施例2.12
本实施例的操作同实施例2.1，区别仅在于：采用载体5代替载体1进行加氢脱氯催化剂 的制备，S2步骤中，活性金属离子还原3小时，制备获得的催化剂记为cat2.12。
经TEM表征，所述cat2.12中98％的活性金属粒子呈包裹型双金属结构。
实施例2.13
本实施例的操作同实施例2.1，区别仅在于：采用载体5代替载体1进行加氢脱氯催化剂的制备，S2步骤中，第二金属离子还原温度200℃，制备获得的催化剂记为cat2.13。
经TEM表征，所述cat2.13中93％的活性金属粒子呈包裹型双金属结构。
实施例2.14
本实施例的操作同实施例2.1，区别仅在于：采用载体5代替载体1进行加氢脱氯催化剂的制备，S2步骤中，第二金属离子还原压力3.0MPa，制备获得的催化剂记为cat2.14。
经TEM表征，所述cat2.14中93％的活性金属粒子呈包裹型双金属结构。
实施例2.15
本实施例的操作同实施例2.1，区别仅在于：采用载体13代替载体1进行加氢脱氯催化剂的制备，S3步骤中，恒温干燥时间为3小时，制备获得的催化剂记为cat2.15。
经TEM表征，所述cat2.15中97％的活性金属粒子呈包裹型双金属结构。
实施例2.16
本实施例的操作同实施例2.1，区别仅在于：采用载体14代替载体1进行加氢脱氯催化剂的制备，S3步骤中，升温速率改为1.5℃/min，制备获得的催化剂记为cat2.16。
经TEM表征，所述cat2.16中91％的活性金属粒子呈包裹型双金属结构。
实施例2.17
本实施例的操作同实施例2.1，区别仅在于：采用载体15代替载体1进行加氢脱氯催化剂的制备，S3步骤中，升温终温改为140℃，制备获得的催化剂记为cat2.17。
经TEM表征，所述cat2.17中96％的活性金属粒子呈包裹型双金属结构。
实施例2.18
本实施例的操作同实施例2.1，区别仅在于：采用载体16代替载体1进行加氢脱氯催化剂的制备，S4步骤中，升温终温改为400℃，制备获得的催化剂记为cat2.18。
经TEM表征，所述cat2.18中93％的活性金属粒子呈包裹型双金属结构。
实施例2.19
本实施例的操作同实施例2.1，区别仅在于：采用载体17代替载体1进行加氢脱氯催化 剂的制备，S4步骤中，升温速率改为1.5℃/min，制备获得的催化剂记为cat2.19。
经TEM表征，所述cat2.19中94％的活性金属粒子呈包裹型双金属结构。
实施例2.20
本实施例的操作同实施例2.1，区别仅在于：采用载体6代替载体1进行加氢脱氯催化剂的制备，S4步骤中，恒温时间改为3小时，制备获得的催化剂记为cat2.20。
经TEM表征，所述cat12.20中91％的活性金属粒子呈包裹型双金属结构。
对比例2.1
本对比例的操作同实施例2.1，区别仅在于：采用柱状活性炭代替整体式堇青石载体，制备获得的催化剂记为B2.1，56％的活性金属粒子呈包裹型双金属结构。
对比例2.2
本对比例的操作同实施例2.1，区别仅在于：S1步骤中从浸渍液中取出的整体式堇青石载体直接置于氮气流中吹扫，省略静置沥干过程。制备获得的催化剂记为B2.2，54％的活性金属粒子呈包裹型双金属结构。
对比例2.3
本对比例的操作同实施例2.1，区别仅在于：S1步骤中从浸渍液中取出的整体式堇青石载体在静置沥干后，未经氮气流吹扫，直接进行第二金属负载。制备获得的催化剂记为B2.3，58％的活性金属粒子呈包裹型双金属结构。
对比例2.4
本对比例的操作同实施例2.1，区别仅在于：S2步骤中，在乙二醇溶液中未通入氢气，直接升温至250℃，升压至1.0MPa进行第二金属负载，未进行活性金属还原步骤。制备获得的催化剂记为B2.4，15％的活性金属粒子呈包裹型双金属结构。
对比例2.5
本对比例的操作同实施例2.1，区别仅在于：S2步骤中，仅在活性金属还原步骤通入氢气，第二金属浸渍时停止通入氢气。制备获得的催化剂记为B2.5，25％的活性金属粒子呈包裹型双金属结构。
对比例2.6
本对比例的操作同实施例2.1，区别仅在于：S2步骤中第二金属负载时，改为常温常压反应，而非250℃、1.0MPa的反应条件。制备获得的催化剂记为B2.6，43％的活性金属粒子 呈包裹型双金属结构。
对比例2.7
本对比例的操作同实施例2.1，区别仅在于：S2步骤中采用甲醇代替乙二醇溶液，制备获得的催化剂记为B2.7，31％的活性金属粒子呈包裹型双金属结构。
对比例2.8
本对比例的操作同实施例2.1，区别仅在于：本对比例制备过程中不采用载体，具体过程包括：将氯钯酸溶液加入到乙二醇溶液中，并在搅拌状态下持续通入氢气；加入氯化铜溶液混合，升温升压反应；在氮气气氛下恒温干燥；在氢气气氛下还原。制备获得的催化剂记为B2.8，得到的金属粒子尺寸为60～700nm，大小分布不均，23％的活性金属粒子呈包裹型双金属结构。
对比例2.9
本对比例的操作同实施例2.1，区别仅在于：所述整体式堇青石载体制备不掺杂氮(未添加乙二胺)。制备获得的催化剂记为B2.9，57％的活性金属粒子呈包裹型双金属结构。
对比例2.10
将整体式堇青石载体4用去离子水冲洗干净后，浸没于氯钯酸和氯化铜水溶液中，钯和铜的含量为整体式堇青石载体的1.0％和1.0％，浸渍液总体积与整体式堇青石载体的体积比为2:1。开启搅拌，升温至50℃，浸渍3小时后取出。在30℃、空气湿度70％下静置15小时沥干，然后用流速为0.5m/s的氮气流(含0.1v/v氧气)吹扫1小时。
干燥与还原步骤的操作同实施例2.1中的干燥与还原步骤。
制备获得的催化剂记为B2.10，经TEM表征，钯铜双金属没有形成包裹型核壳结构，为双金属合金状态。
实施例2.21
本实施例为加氢脱氯催化剂在三氟三氯乙烷加氢脱氯制备三氟氯乙烯反应中的应用，具体步骤如下：
将0.5g实施例2.1制备获得的Cat2.1装入固定床反应器中，反应器内径10mm。升温至250℃，通入摩尔比为1:1的氢气与三氟三氯乙烷组成的混合气，空速为300h -1，250℃下反应。
加氢产物用Agilent 7890A气相色谱分析，结果显示转化率100％，三氟氯乙烯选择性 99.58％。
实施例2.22-2.48
实施例2.22-2.48的操作同实施例2.1，区别仅在于：采用实施例2.2-2.20、对比例2.1-2.10制备获得的催化剂代替cat2.1进行加氢脱氯反应。
加氢产物用Agilent 7890A气相色谱分析，分析结果如下表5所示：
表5不同催化剂下三氟三氯乙烷加氢脱氯反应结果
Figure PCTCN2021117089-appb-000005
Figure PCTCN2021117089-appb-000006
实施例2.49-2.72
实施例2.49-2.72的操作步骤同实施例2.22，采用Cat2.3作为加氢脱氯催化剂，改变反应条件进行加氢脱氯反应。
加氢产物用Agilent 7890A气相色谱分析，分析结果如下表6所示：
表6不同反应条件下三氟三氯乙烷加氢脱氯反应结果
Figure PCTCN2021117089-appb-000007
实施例2.73
实施例2.73是在实施例2.56的反应条件下进行的稳定性实验。
加氢产物用Agilent 7890A气相色谱分析，分析结果如下表7所示：
表7加氢脱氯反应稳定性结果
时间/天 转化率/％ 选择性/％
10 100 99.67
20 100 99.64
30 100 99.77
40 100 99.68
50 100 99.58
60 100 99.57
70 100 99.58
80 100 99.70
90 100 99.57
100 100 99.56
110 100 99.71
120 100 99.58
130 100 99.59
140 100 99.55
150 100 99.77
160 100 99.80
170 100 99.69
180 100 99.57
(第三方面)、本发明实施例第三种核壳结构的加氢脱氯催化剂的制备及应用。
实施例3.1
加氢脱氯催化剂的制备：
S1.活性金属粒子制备：按1.5wt％的负载量配制氯铂酸水溶液，加入5.0wt％的乙二醇水溶液，进行超声浸渍，浸渍温度为35℃，超声波频率30kHz，功率300w，超声浸渍1小时后离心分离，并采用去离子水洗涤(多次洗涤)至中性，获得活性金属粒子；
S2.第二金属粒子包裹：将活性金属粒子、按2.0wt％负载量配制的氯化铜溶液加入25wt％的乙二醇溶液中，所述乙二醇和第二金属的质量比为1:30，第二金属盐浓度为0.1mol/L；搅拌状态下通入氢气，搅拌转速为3000r/min，氢气压力维持2.0MPa，控制温度200℃，反应5小时后离心分离，并采用去离子水洗涤(多次洗涤)至中性，获得包裹型双金属粒子；
S3.双金属粒子负载：将所述包裹型双金属粒子置于去离子水中，超声5分钟，在3000r/min的速度下搅拌1小时，之后加入事先用去离子水冲洗干净的活性炭载体(木质，比表面积1200m 2/g，灰份1.5wt％)，所述活性炭载体的体积与浸渍液的体积比为1:5，80℃下浸渍3小时，过滤，用去离子水洗涤至中性，获得活性炭负载的双金属粒子(密封保存)；
S4.干燥：将活性炭负载的双金属粒子置于管式炉内，在氮气气氛下(空速为300h -1)以0.5℃/min的速率从室温升至150℃，恒温干燥2小时获得催化剂前体。
S5.还原：将获得的催化剂前体在氢气气氛下(空速为300h -1)，以0.1℃/min的速率从室温升温至250℃，恒温1小时，获得所述加氢脱氯催化剂，记为cat3.1。
图1给出了本实施制备获得的加氢脱氯催化剂的TEM表征图，从图中看出，本实施例的加氢脱氯催化剂形成包裹型结构，核为钯，壳为铜。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，85％的活性金属粒子呈包裹型双金属结构。
实施例3.2
本实施例的操作同实施例3.1，区别仅在于：活性金属负载量降低至1.0％，第二金属负载量降低至1.5％，制备获得加氢脱氯催化剂，记为cat3.2。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，82％的活性金属粒子呈包裹型双金属结构。
实施例3.3
本实施例的操作同实施例3.1，区别仅在于：活性金属负载量为1.5％，第二金属负载量降低至4.5％，制备获得加氢脱氯催化剂，记为cat3.3。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，94％的活性金属粒子呈包裹型双金属结构。
实施例3.4
本实施例的操作同实施例3.1，区别仅在于：活性金属为铂，第二金属改为锌。制备获得加氢脱氯催化剂，记为cat3.4。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，95％的活性金属粒子呈包裹型双金属结构。
实施例3.5
本实施例的操作同实施例3.1，区别仅在于：活性金属改为镍，第二金属改为锌。制备获得加氢脱氯催化剂，记为cat3.5。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，88％的活性金属粒子呈包裹型双金属结构。
实施例3.6
本实施例的操作同实施例3.1，区别仅在于：活性金属溶液(活性金属前驱体)采用硝酸 钯，第二金属溶液采用氯化锌。制备获得加氢脱氯催化剂，记为cat3.6。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，89％的活性金属粒子呈包裹型双金属结构。
实施例3.7
本实施例的操作同实施例3.1，区别仅在于：活性金属溶液(活性金属前驱体)采用氯钯酸，第二金属溶液采用硝酸锌。制备获得加氢脱氯催化剂，记为cat3.7。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，87％的活性金属粒子呈包裹型双金属结构。
实施例3.8
本实施例的操作同实施例3.1，区别仅在于：S1步骤中，浸渍温度为升高为60℃。制备获得加氢脱氯催化剂，记为cat3.8。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，96％的活性金属粒子呈包裹型双金属结构。
实施例3.9
本实施例的操作同实施例3.1，区别仅在于：S1步骤中，浸渍时间增加至6小时。制备获得加氢脱氯催化剂，记为cat3.9。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，90％的活性金属粒子呈包裹型双金属结构。
实施例3.10
本实施例的操作同实施例3.1，区别仅在于：S2步骤中，双金属粒子还原时，氢气压力为1.5MPa。制备获得加氢脱氯催化剂，记为cat3.10。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，88％的活性金属粒子呈包裹型双金属结构。
实施例3.11
本实施例的操作同实施例3.1，区别仅在于：S2步骤中，双金属粒子还原时间降为3小时。制备获得加氢脱氯催化剂，记为cat3.11。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，94％的活性金属粒子呈包裹型双金属结构。
实施例3.12
本实施例的操作同实施例3.1，区别仅在于：S2步骤中，温度为150。制备获得加氢脱氯催化剂，记为cat3.12。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，88％的活性金属粒子呈包裹型双金属结构。
实施例3.13
本实施例的操作同实施例3.1，区别仅在于：S2步骤中，乙二醇的质量和第二金属的质量比为1:60。制备获得加氢脱氯催化剂，记为cat3.13。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，90％的活性金属粒子呈包裹型双金属结构。
实施例3.14
本实施例的操作同实施例3.1，区别仅在于：S3步骤中，搅拌转速降低为2000r/min。制备获得加氢脱氯催化剂，记为cat3.14。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，95％的活性金属粒子呈包裹型双金属结构。
实施例3.15
本实施例的操作同实施例3.1，区别仅在于：S3步骤中，搅拌时间增加至2小时。制备获得加氢脱氯催化剂，记为cat3.15。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，95％的活性金属粒子呈包裹型双金属结构。
实施例3.16
本实施例的操作同实施例3.1，区别仅在于：S3步骤中，超声15分钟。制备获得加氢脱氯催化剂，记为cat3.16。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，93％的活性金属粒子呈包裹型双金属结构。
实施例3.17
本实施例的操作同实施例3.1，区别仅在于：S3步骤中，活性炭于浸渍液比例为1：3。制备获得加氢脱氯催化剂，记为cat3.17。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，92％的活性金属粒子呈包裹型双金属结构。
实施例3.18
本实施例的操作同实施例3.1，区别仅在于：S4干燥步骤中恒温干燥时间增加至3小时。制备获得加氢脱氯催化剂，记为cat3.18。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，91％的活性金属粒子呈包裹型双金属结构。
实施例3.19
本实施例的操作同实施例3.1，区别仅在于：S4干燥步骤中升温速率为1.25℃/min。制备获得加氢脱氯催化剂，记为cat3.19。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，93％的活性金属粒子呈包裹型双金属结构。
实施例3.20
本实施例的操作同实施例3.1，区别仅在于：S5步骤中，催化剂前驱体在氢气气氛下还原恒温时间增加至2小时。制备获得加氢脱氯催化剂，记为cat3.20。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，93％的活性金属粒子呈包裹型双金属结构。
实施例3.21
本实施例的操作同实施例3.1，区别仅在于：S5步骤中，升温速率为1.0℃/min。制备获得加氢脱氯催化剂，记为cat3.21。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，90％的活性金属粒子呈包裹型双金属结构。
实施例3.22
本实施例的操作同实施例3.1，区别仅在于：S5步骤中，终温为400℃。制备获得加氢脱氯催化剂，记为cat3.22。
经TEM表征，本实施制备获得的加氢脱氯催化剂中，94％的活性金属粒子呈包裹型双金属结构。
对比例3.1
本对比例的操作同实施例3.1，区别仅在于：活性金属粒子制备过程中不采用超声处理，制备获得的催化剂记为B3.1，46％的活性金属粒子呈包裹型双金属结构。
对比例3.2
本对比例的操作同实施例3.1，区别仅在于：第二金属粒子包裹过程中，控制温度80℃，制备获得的催化剂记为B3.2，42％的活性金属粒子呈包裹型双金属结构。
对比例3.3
本对比例的操作同实施例3.1，区别仅在于：第二金属粒子包裹过程中，控制温度350℃，制备获得的催化剂记为B3.3，51％的活性金属粒子呈包裹型双金属结构。
对比例3.4
本对比例的操作同实施例3.1，区别仅在于：第二金属粒子包裹过程中，未通入氢气，制备获得的催化剂记为B3.4，41％的活性金属粒子呈包裹型双金属结构。
对比例3.5
本对比例的操作同实施例3.1，区别仅在于：第二金属粒子包裹过程中，未加入乙二醇溶液，制备获得的催化剂记为B3.5，58％的活性金属粒子呈包裹型双金属结构。
对比例3.6
本对比例的操作同实施例3.1，区别仅在于：第二金属粒子包裹过程中，采用甲醇代替乙二醇溶液，制备获得的催化剂记为B3.6，43％的活性金属粒子呈包裹型双金属结构。
对比例3.7
本对比例的操作同实施例3.1，区别仅在于：省略S3双金属粒子负载步骤，制备的催化剂不采用载体进行负载。制备获得的催化剂记为B3.7，得到的金属粒子尺寸70～600nm，大小分布不均，59％的活性金属粒子呈包裹型双金属结构。
对比例3.8
本对比例的操作同实施例3.1，区别仅在于：没有对获得的催化剂前体进行还原，制备获得的催化剂记为B3.8，47％的活性金属粒子呈包裹型双金属结构。
对比例3.9
将活性炭载体(木质，比表面积1200m 2/g，灰份1.5wt％)用去离子水冲洗干净后，浸没于氯钯酸和氯化铜水溶液中，钯和铜的含量为活性炭载体的1.5％和2.0％，浸渍液总体积与活性炭载体的体积比为5:1。开启搅拌，升温至50℃，浸渍3小时后取出，110℃烘干4小 时。
干燥与还原步骤的操作同实施例3.1中的干燥与还原步骤。
制备获得的催化剂记为B3.9，经TEM表征，钯铜双金属没有形成包裹型核壳结构，为双金属合金状态。
实施例3.23
本实施例为加氢脱氯催化剂在三氟三氯乙烷加氢脱氯制备三氟氯乙烯反应中的应用，具体步骤如下：
将0.5g实施例3.1制备获得的Cat3.1(粒度0.5～1mm)装入固定床反应器中，反应器内径10mm。升温至250℃，通入摩尔比为1:1的氢气与三氟三氯乙烷组成的混合气，空速为300h -1，250℃下反应。
加氢产物用Agilent 7890A气相色谱分析，结果显示转化率100％，三氟氯乙烯选择性99.38％。
实施例3.24-3.46
实施例3.24-3.46的操作同实施例3.23，区别仅在于：采用实施例3.2～3.15、对比例3.1～3.9制备获得的催化剂代替cat3.1进行加氢脱氯反应。
加氢产物用Agilent 7890A气相色谱分析，分析结果如下表8所示：
表8不同催化剂下三氟三氯乙烷加氢脱氯反应结果
Figure PCTCN2021117089-appb-000008
Figure PCTCN2021117089-appb-000009
实施例3.47-3.68
实施例3.47-3.68的操作步骤同实施例3.30，区别仅在于：采用Cat3.8作为加氢脱氯催化剂，改变反应条件进行加氢脱氯反应。
加氢产物用Agilent 7890A气相色谱分析，分析结果如下表9所示：
表9不同反应条件下三氟三氯乙烷加氢脱氯反应结果
Figure PCTCN2021117089-appb-000010
Figure PCTCN2021117089-appb-000011
实施例3.69
实施例3.69是在实施例3.26的反应条件下进行的稳定性实验。
加氢产物用Agilent 7890A气相色谱分析，分析结果如下表10所示：
表10加氢脱氯反应稳定性结果
时间/天 转化率/％ 选择性/％
10 100 99.53
20 100 99.74
30 100 99.72
40 100 99.28
50 100 99.68
60 100 99.57
70 100 99.68
80 100 99.70
90 100 99.68
100 100 99.59
110 100 99.81
120 100 99.48
130 100 99.49
140 100 99.55
150 100 99.67
160 100 99.90
170 100 99.65
180 100 99.58

Claims (39)

  1. 一种核壳结构的加氢脱氯催化剂，其特征在于：所述催化剂包括：
    载体，所述载体为整体式活性炭载体；
    负载于载体的活性金属，所述活性金属选自钯、铂、铱、镍的至少一种；
    负载于载体的第二金属，所述第二金属选自铜、锡、银、锌中的一种；
    所述催化剂呈包裹型结构，核部为活性金属，壳层为第二金属。
  2. 根据权利要求1所述的核壳结构的加氢脱氯催化剂，其特征在于：所述活性金属的负载量为0.05～5.0％，第二金属的负载量为0.01～4.0％，且第二金属的负载量不高于活性金属。
  3. 根据权利要求2所述的核壳结构的加氢脱氯催化剂，其特征在于：活性金属与第二金属的质量比为1～6:1。
  4. 根据权利要求1所述的核壳结构的加氢脱氯催化剂，其特征在于：所述核部活性金属粒子尺寸≤90nm，壳层厚度≤5nm。
  5. 根据权利要求1所述的核壳结构的加氢脱氯催化剂，其特征在于：所述整体式活性炭载体的比表面积≥900m 2/g，灰份≤3.0wt％，孔密度为10～50孔/cm 2，密度为0.1～0.8g/mL。
  6. 权利要求1-5任一所述核壳结构的加氢脱氯催化剂的制备方法，其特征在于：所述制备方法包括以下步骤：
    A1.活性金属负载
    将整体式活性炭载体浸渍于活性金属盐溶液中形成浸渍液，在25～85℃下浸渍2～6小时后取出，静置沥干，采用氮气流吹扫；
    A2.第二金属负载
    将负载有活性金属的整体式活性炭载体浸没于乙二醇中，并在乙二醇中通入氢气，搅拌，控制温度为20～95℃，压力为0.1～0.5Mpa，时间为1～10小时；滴入第二金属盐溶液，升温升压反应，反应温度为100～250℃，反应压力为0.1～2.0Mpa，反应时间为3～10小时，反应结束后取出沥干；
    A3.干燥
    将负载有活性金属和第二金属的整体式活性炭载体置于氮气气氛下，以0.5～2.0℃/min的速率从室温开始升温，至110～150℃后恒温干燥2～5小时，获得催化剂前体；
    A4.还原
    将催化剂前体置于氢气气氛下，以0.1～2.0℃/min的速率升温至250～450℃，恒温1～5 小时，获得所述加氢脱氯催化剂。
  7. 根据权利要求6所述核壳结构的加氢脱氯催化剂的制备方法，其特征在于：所述活性金属盐溶液为活性金属硝酸盐溶液或活性金属氯化物溶液；所述第二金属盐溶液为第二金属硝酸盐溶液或第二金属氯化物溶液，溶液浓度为0.5～2.0mol/L。
  8. 根据权利要求6所述核壳结构的加氢脱氯催化剂的制备方法，其特征在于：所述浸渍液的总体积与整体式活性炭载体的体积比为2～5:1。
  9. 根据权利要求6所述核壳结构的加氢脱氯催化剂的制备方法，其特征在于：在20～35℃、空气湿度≤80％的环境下静置10～20小时，沥干，再在流速为0.1～2.0m/s、含0.1～1.0v/v％氧气的氮气流中吹扫0.5～2小时。
  10. 根据权利要求6-9任一所述核壳结构的加氢脱氯催化剂的制备方法，其特征在于：制备获得的所述加氢脱氯催化剂中，≥85％的第二金属粒子呈包裹型双金属结构。
  11. 一种整体式堇青石载体加氢脱氯催化剂，其特征在于：所述催化剂包括：
    载体，所述载体为整体式堇青石载体；
    负载于载体的活性金属，所述活性金属选自钯、铂、铱、镍的至少一种；
    负载于载体的第二金属，所述第二金属选自铜、锡、银、锌中的一种；
    所述催化剂为呈核壳结构的包裹型双金属粒子，核部为活性金属，壳层为第二金属。
  12. 根据权利要求11所述的整体式堇青石载体加氢脱氯催化剂，其特征在于：所述整体式堇青石载体为氮掺杂炭涂覆的整体式堇青石载体，氮掺杂炭涂层的质量占整体式堇青石载体的0.1～5.0wt％，氮含量占炭涂层质量的0.1～8.0wt％。
  13. 根据权利要求12所述的整体式堇青石载体加氢脱氯催化剂，其特征在于：所述整体式堇青石载体的孔密度为10～50孔/cm 2，比表面积≥900m 2/g。
  14. 根据权利要求11所述的整体式堇青石载体加氢脱氯催化剂，其特征在于：所述活性金属的负载量为0.01～4.5％，第二金属的负载量为0.01～5.5％，且第二金属的负载量不低于活性金属。
  15. 根据权利要求4所述的整体式堇青石载体加氢脱氯催化剂，其特征在于：所述活性金属与第二金属的质量比为1:1～5。
  16. 根据权利要求11所述的整体式堇青石载体加氢脱氯催化剂，其特征在于：所述核部活性金属粒子尺寸≤100nm，壳层厚度≤5nm。
  17. 权利要求11-16任一所述整体式堇青石载体加氢脱氯催化剂的制备方法，其特征在于：所述制备方法包括以下步骤：
    A1.活性金属负载
    将氮掺杂炭涂覆的整体式堇青石载体浸渍于活性金属盐溶液形成的浸渍液，在25～85℃下浸渍2～6小时后取出，静置沥干，采用氮气流吹扫；所述浸渍液的总体积与整体式堇青石载体的体积比为2～5:1；
    A2.第二金属负载
    将负载有活性金属的整体式堇青石载体浸没于乙二醇中，并在乙二醇中通入氢气，搅拌，控制温度为20～95℃，压力为0.1～0.2Mpa，时间为1～10小时；
    滴入第二金属盐溶液，升温升压反应，反应温度为150～350℃，反应压力为0.5～4.0Mpa，反应时间为3～10小时，反应结束后取出沥干；
    A3.干燥
    将负载有活性金属和第二金属的整体式堇青石载体置于氮气气氛下，以0.5～2.0℃/min的速率从室温开始升温，至110～150℃后恒温干燥2～5小时，获得催化剂前体；
    A4.还原
    将催化剂前体置于氢气气氛下，以0.1～2.0℃/min的速率升温至250～450℃，恒温1～5小时，获得所述加氢脱氯催化剂。
  18. 根据权利要求17所述整体式堇青石载体加氢脱氯催化剂的制备方法，其特征在于：所述氮掺杂炭涂覆的整体式堇青石载体表面的氮掺杂炭涂层的涂覆方法包括以下步骤：
    将淀粉、葡萄糖、乙二胺与水按1：1～3：1～3：1～2的质量比配制成水溶液，将整体式堇青石载体浸没其中，均匀涂覆在整体式堇青石载体表面后取出，在110～150℃下恒温干燥2～3小时，再在氮气气氛中，于400～800℃焙烧3～8小时，即可获得氮掺杂炭涂覆的整体式堇青石载体。
  19. 根据权利要求18所述整体式堇青石载体加氢脱氯催化剂的制备方法，其特征在于：整体式堇青石载体经2～5次的重复浸渍涂覆、干燥和焙烧后，获得氮掺杂炭涂覆的堇青石载体。
  20. 根据权利要求17所述整体式堇青石载体加氢脱氯催化剂的制备方法，其特征在于：所述活性金属盐溶液为活性金属硝酸盐溶液或活性金属氯化物溶液；所述第二金属盐溶液为 第二金属硝酸盐溶液或第二金属氯化物溶液，溶液浓度为0.5～2.0mol/L。
  21. 根据权利要求17所述整体式堇青石载体加氢脱氯催化剂的制备方法，其特征在于：在活性金属负载步骤中，在20～35℃、空气湿度≤80％的环境下静置10～20小时，沥干，再在流速为0.1～2.0m/s、含0.1～1.0v/v％氧气的氮气流中吹扫0.5～2小时。
  22. 根据权利要求17-21任一所述整体式堇青石载体加氢脱氯催化剂的制备方法，其特征在于：制备获得的所述加氢脱氯催化剂中，≥90％的活性金属粒子呈包裹型双金属结构。
  23. 一种高选择性加氢脱氯催化剂，其特征在于：所述催化剂包括：
    载体，所述载体为活性炭；
    负载于载体的活性金属，所述活性金属选自钯、铂、铱、镍的至少一种；
    负载于载体的第二金属，所述第二金属选自铜、锡、银、锌中的一种；
    所述催化剂为呈核壳结构的包裹型双金属粒子，核部为活性金属，壳层为第二金属。
  24. 根据权利要求23所述的高选择性加氢脱氯催化剂，其特征在于：所述活性金属的负载量为0.05～5.0％，第二金属的负载量为0.1～8.0％，且第二金属的负载量不低于活性金属。
  25. 根据权利要求24所述的高选择性加氢脱氯催化剂，其特征在于：活性金属与第二金属的质量比为1：1～6。
  26. 根据权利要求23所述的高选择性加氢脱氯催化剂，其特征在于：所述核部活性金属粒子尺寸≤65nm，壳层厚度≤10nm。
  27. 根据权利要求23所述的高选择性加氢脱氯催化剂，其特征在于：所述载体为颗粒状活性炭或柱状活性炭，比表面积≥1000m 2/g，灰份≤3.0wt％。
  28. 权利要求23-27任一所述高选择性加氢脱氯催化剂的制备方法，其特征在于：所述制备方法包括以下步骤：
    A1.活性金属粒子制备
    按负载量配置活性金属盐的浸渍液，在25～95℃，超声下浸渍0.5～10小时后离心分离，获得活性金属粒子；所述浸渍液为乙二醇水溶液、甲醛水溶液或葡萄糖水溶液中的至少一种；
    A2.第二金属粒子包裹
    将活性金属粒子、按负载量配置的第二金属盐溶液加入还原试剂中，搅拌下通入氢气，氢气压力为0.1～2.0MPa，控制温度100～300℃，1～10小时后离心分离，获得包裹型双金属粒子；
    A3.双金属粒子负载
    将所述包裹型双金属粒子置于去离子水中，搅拌状态下加入活性炭载体，浸渍、过滤、洗涤，获得活性炭负载的双金属粒子；浸渍温度为20～80℃，浸渍时间为1～10小时；
    A4.干燥
    将活性炭负载的双金属粒子置于氮气气氛下，以0.5～2.0℃/min的速率从室温开始升温，至110～150℃后恒温干燥2～5小时，获得催化剂前体；
    A5.还原
    将催化剂前体置于氢气气氛下，以0.1～2.0℃/min的速率升温至250～450℃，恒温1～5小时，获得所述加氢脱氯催化剂。
  29. 根据权利要求28所述高选择性加氢脱氯催化剂的制备方法，其特征在于：所述A1步骤的超声频率为30～50kHz，功率为300～1000w。
  30. 根据权利要求28所述高选择性加氢脱氯催化剂的制备方法，其特征在于：所述活性金属盐为活性金属硝酸盐或活性金属氯化物；第二金属盐溶液为第二金属硝酸盐溶液或第二金属氯化物溶液，浓度为0.1～2.0mol/L。
  31. 根据权利要求28所述高选择性加氢脱氯催化剂的制备方法，其特征在于：乙二醇水溶液、甲醛水溶液或葡萄糖水溶液的质量含量为1～20wt％。
  32. 根据权利要求28所述高选择性加氢脱氯催化剂的制备方法，其特征在于：所述还原试剂为乙二醇、硼氢化钠或水合肼中的至少一种，且所述还原试剂与第二金属的质量比为1:20～100。
  33. 根据权利要求32所述高选择性加氢脱氯催化剂的制备方法，其特征在于：所述还原试剂为质量含量为5～50wt％的还原试剂水溶液。
  34. 根据权利要求28所述高选择性加氢脱氯催化剂的制备方法，其特征在于：A3步骤中将包裹型双金属粒子置于去离子水中，超声5～20分钟、搅拌0.5～1小时后，在搅拌状态下加入活性炭载体。
  35. 根据权利要求28所述高选择性加氢脱氯催化剂的制备方法，其特征在于：A1步骤和A2步骤中离心分离后均采用去离子水洗涤至中性。
  36. 根据权利要求28-35任一所述高选择性加氢脱氯催化剂的制备方法，其特征在于：制备获得的所述加氢脱氯催化剂中，≥80％的活性金属粒子呈包裹型双金属结构。
  37. 一种三氟氯乙烯的连续制备方法，其特征在于：采用权利要求1-5任一所述的核壳结构的加氢脱氯催化剂，或权利要求11-16任一所述的整体式堇青石载体加氢脱氯催化剂，或权利要求23-27任一所述的高选择性加氢脱氯催化剂，以三氟三氯乙烷和氢气为原料经加氢脱氯反应制备获得三氟氯乙烯。
  38. 根据权利要求37所述的三氟氯乙烯的连续制备方法，其特征在于：三氟三氯乙烷与氢气的摩尔比为：1：1～4。
  39. 根据权利要求37所述的三氟氯乙烯的连续制备方法，其特征在于：采用权利要求1-5任一所述的核壳结构的加氢脱氯催化剂时，反应温度为150～300℃，原料空速为10～1300h -1；采用权利要求11-16任一所述的整体式堇青石载体加氢脱氯催化剂时，反应温度为150～300℃，原料空速为10～1500h -1；采用权利要求23-27任一所述的高选择性加氢脱氯催化剂时，反应温度为150～300℃，原料空速为10～1200h -1。
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115582138A (zh) * 2022-10-16 2023-01-10 宁夏新龙蓝天科技股份有限公司 可再生反应氯乙烯合成用无汞催化剂及其制备方法

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1065261A (zh) * 1991-01-25 1992-10-14 索尔维公司 制备一氯三氟乙烯和三氟乙烯的方法以及用于该方法的催化剂组合物
CN101143328A (zh) * 2007-10-26 2008-03-19 江苏工业学院 一种用于制备四氯乙烯的催化剂及其制备方法与用途
WO2018078652A1 (en) * 2016-10-26 2018-05-03 Council Of Scientific And Industrial Research An improved process for the preparation of bimetallic core-shell nanoparticles and their catalytic applications
CN108579758A (zh) * 2018-03-23 2018-09-28 中国科学院宁波材料技术与工程研究所 一种可控的双金属核壳纳米结构、催化剂、其制法与应用
CN112657525A (zh) * 2021-01-21 2021-04-16 中化蓝天集团有限公司 一种整体式堇青石载体加氢脱氯催化剂、其制备方法及应用
CN112657507A (zh) * 2020-12-04 2021-04-16 中化蓝天集团有限公司 一种高选择性加氢脱氯催化剂、其制备方法及应用
CN112657508A (zh) * 2020-12-04 2021-04-16 中化蓝天集团有限公司 一种核壳结构的加氢脱氯催化剂、其制备方法及应用

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1065261A (zh) * 1991-01-25 1992-10-14 索尔维公司 制备一氯三氟乙烯和三氟乙烯的方法以及用于该方法的催化剂组合物
CN101143328A (zh) * 2007-10-26 2008-03-19 江苏工业学院 一种用于制备四氯乙烯的催化剂及其制备方法与用途
WO2018078652A1 (en) * 2016-10-26 2018-05-03 Council Of Scientific And Industrial Research An improved process for the preparation of bimetallic core-shell nanoparticles and their catalytic applications
CN108579758A (zh) * 2018-03-23 2018-09-28 中国科学院宁波材料技术与工程研究所 一种可控的双金属核壳纳米结构、催化剂、其制法与应用
CN112657507A (zh) * 2020-12-04 2021-04-16 中化蓝天集团有限公司 一种高选择性加氢脱氯催化剂、其制备方法及应用
CN112657508A (zh) * 2020-12-04 2021-04-16 中化蓝天集团有限公司 一种核壳结构的加氢脱氯催化剂、其制备方法及应用
CN112657525A (zh) * 2021-01-21 2021-04-16 中化蓝天集团有限公司 一种整体式堇青石载体加氢脱氯催化剂、其制备方法及应用

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115582138A (zh) * 2022-10-16 2023-01-10 宁夏新龙蓝天科技股份有限公司 可再生反应氯乙烯合成用无汞催化剂及其制备方法

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