Carbon deposition prevention catalyst, preparation method, and applications
The carbon deposition prevention catalyst, using platinum or palladium with zinc, copper, or cobalt and ruthenium or nickel additives, addresses carbon deposition issues in chlorotrifluoroethylene synthesis, ensuring high dechlorination performance and extended catalyst life.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- SINOCHEM LANTIAN CO LTD
- Filing Date
- 2023-03-03
- Publication Date
- 2026-07-08
AI Technical Summary
Existing catalysts for chlorotrifluoroethylene synthesis suffer from carbon deposition issues that affect catalyst stability and lifespan, and current methods to remove carbon deposition often damage the catalyst structure.
A carbon deposition prevention catalyst composed of a carbon carrier, platinum or palladium as the metal active component, and zinc, copper, or cobalt, and ruthenium or nickel as metal additives, with specific mass ratios and preparation steps to enhance catalyst stability.
The catalyst effectively prevents carbon deposition, maintaining high dechlorination performance and extending catalyst lifespan by forming multifunctional active centers and reducing acidity at the catalyst surface.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to the field of catalysts, and particularly to a carbon deposition prevention catalyst, a preparation method and an application thereof.
Background Art
[0002] Chlorotrifluoroethylene is a colorless gas with a slight ether odor, has excellent reactivity, is an important fluorine-containing polymerization monomer, and is also an important chemical intermediate, and is widely used in fields such as pesticides, medicine, and polymer materials.
[0003] Chinese Patent Application CN1110103604A discloses a catalyst for catalytic hydrogenation dechlorination, a preparation method and an application thereof. In this method, the alloy catalyst is mainly composed of the element Ru, and any one or more of the specified alloy elements Re, Ti, Cr, Ni, Al, Co, Cu, Nb, Ta, Ru, Pt or Ag are selected to form an alloy with Ru, the promoter is an alkali metal or an alkaline earth metal, and the carrier is an activated carbon carrier. When it is used in the preparation of chlorotrifluoroethylene, the conversion rate of chlorotrifluoroethylene is about 95.7% and the selectivity is 95.6%.
[0004] However, in the synthesis of CTFE by catalytic hydrogenation, there is an important core problem of how to suppress carbon deposition. The presence of carbon deposition does not affect the raw material conversion rate and product selectivity in the initial stage of the reaction, but has a great impact on the stability and life of the catalyst. Existing literature reports that carbon deposition is mainly affected by the acidity of the catalytic active sites and the reaction temperature. Therefore, by reducing the acidity of the active sites or increasing the catalytic activity (lowering the reaction temperature), carbon deposition can be effectively suppressed and the life of the catalyst can be extended.
[0005] Chinese Patent Application CN1589970A discloses a method for regenerating a catalyst for producing alkenyl aromatics by dehydrogenation of alkyl aromatic hydrocarbons. In this method, steam and air are used to regenerate the catalyst by a hydrothermal method, but a higher regeneration temperature is required to completely burn off the carbon attached to the catalyst.
[0006] Chinese Patent Application CN107497420A discloses a method for regenerating a carbon-containing noble metal catalyst. In this method, in the combustion process, the oxygen content in the regeneration gas is controlled step by step, and the carbon deposited on the catalyst is removed by stepwise combustion, and the activity of the catalyst is restored by chlorination and reduction. In the regeneration process of the noble metal catalyst, if the water content is too high during the chlorination operation, the activity of the catalyst will decrease. Therefore, in this method, in order to ensure the regeneration efficiency, it is necessary to strictly control the water content and the maximum operating temperature in the process gas.
[0007] Chinese Patent Application CN107999057A discloses a method for regenerating a supported noble metal catalyst. In this method, the deactivated supported noble metal catalyst is oxidized with a mixed gas of CO2 and O2, and after oxidation, it is reduced with a reducing agent in a tetrahydrofuran solvent to obtain a regenerated catalyst.
[0008] In short, in the conventional catalyst and its catalytic hydrogenation process, the occurrence of carbon deposition cannot be completely suppressed, and carbon deposition can only be removed by regenerating the carbon deposition after it occurs. That is, air, CO2, H2O and other gases are used to chemically react with the carbon deposition to remove the carbon deposition. However, in the process of removing carbon deposition, it is inevitable to damage the carrier carbon, destroy the structure of the catalyst particles, and cause irreversible deactivation of the catalyst. Therefore, it is difficult to control the process of removing carbon deposition.
[0009] So far, there is no relevant report on effectively solving the problem of carbon deposition in the catalytic hydrogenation dechlorination catalyst.
Summary of the Invention
[0010] An object of the present invention is to provide a fluorochloroalkane hydrogenation dechlorination catalyst that can effectively prevent carbon deposition, a preparation method thereof and an application.
[0011] According to one aspect of the present invention, the present invention uses the following technical solutions.
[0012] A carbon deposition prevention catalyst, wherein the catalyst is composed of a carbon carrier, a metal active component, metal additive I, and metal additive II, the metal active component being platinum or palladium, metal additive I being zinc, copper, or cobalt, and metal additive II being ruthenium or nickel, and each type of metal component being only one type of metal.
[0013] The mass content of the metal-active component in the carrier is 0.2-2.0%, and the mass ratio of the metal-active component, metal additive I, and metal additive II is 1:(1-10):(0.01-0.001).
[0014] Preferably, the mass content of the metal-active component in the carrier is 0.2 to 1.5%.
[0015] Preferably, the mass ratio of the metal active component, metal additive I, and metal additive II is 1:(1~8):(0.01~0.003).
[0016] The carbon carrier is activated carbon, preferably in particulate form, and has an ash content of 2% by weight or less.
[0017] According to a second aspect of the present invention, the present invention further provides a method for preparing a carbon deposition prevention catalyst, which specifically includes the following steps.
[0018] A1. Steps for activated carbon treatment Activated carbon is immersed and washed at 50-90°C for 2-6 hours using a sodium hydroxide solution with a molar concentration of 1-5 mol / L, then rinsed with water until neutral. Activated carbon is then immersed and washed at 20-60°C for 2-6 hours using hydrochloric acid with a molar concentration of 0.5-3 mol / L, then rinsed with water until neutral. The ratio of activated carbon to sodium hydroxide solution / hydrochloric acid is 1:1.5-3.0 (g / mL), where g / mL represents immersion washing of 1 g of activated carbon in 1 mL of sodium hydroxide solution / hydrochloric acid.
[0019] The purpose of this step is to remove the metal ash from the activated carbon so that the content of individual metal components is 0.01% by weight or less.
[0020] A2. Preparation of immersion solution The metal active component salt, metal additive I salt, and metal additive II salt are weighed and uniformly mixed in aqueous solutions of ammonium citrate and glycolic acid to form an immersion solution.
[0021] The above-mentioned metal-active component salt, metal additive I salt, and metal additive II salt are all soluble salts. Specifically, the metal-active component salt may be a chloride or nitrate salt of platinum or palladium, for example, platinum dichloride, platinum tetrachloride, and palladium dichloride. The metal additive I salt may be a soluble salt of zinc, copper, or cobalt selected from chloride salts, nitrates, sulfates, or organic salts, such as zinc chloride, copper chloride, cobalt chloride, copper nitrate, cobalt nitrate, zinc sulfate, copper sulfate, cobalt sulfate, zinc acetate, and cobalt acetate. The metal additive II salt may be a soluble salt of ruthenium or nickel, such as hydrated ruthenium trichloride, ruthenium acetate, nickel chloride, nickel nitrate, nickel sulfate, and nickel acetate.
[0022] A3. Activated carbon immersion The activated carbon treated in step A1 is added to the immersion solution in step A2, stirred at 20-50°C for 2-5 hours, then allowed to stand and mature for 5-12 hours, after which the activated carbon is removed and dried. The drying can be done by air drying or oven drying, the volume of the immersion solution is 1.5-2 times the pore volume of the activated carbon, and the immersion is equivolute. The pore volume of the activated carbon is measured by the BET method.
[0023] A4. Steps in catalyst synthesis Activated carbon supporting a metal component is roasted in an inert atmosphere, and the temperature is raised from room temperature to 200-600°C at a rate of 1-5°C / min, and the temperature is kept constant for 2-5 hours to obtain a carbon deposition prevention catalyst. Specifically, the inert gas is nitrogen or argon gas, and the flow rate is 1-10 mL / min.
[0024] By roasting the metal salts, not only can oxides be formed, but the bonding strength between each metal component and between each metal component and the activated carbon support can be strengthened, thereby improving the stability of the catalyst.
[0025] Furthermore, the molar ratio of ammonium citrate to glycolic acid is 1:1 to 3, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:1 to 3. Preferably, the molar ratio of ammonium citrate to glycolic acid is 1:1.5 to 2.5, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:1.5 to 2.5.
[0026] According to a third aspect of the present invention, the present invention further provides applications of the carbon deposition prevention catalyst prepared as described above, specifically, the carbon deposition prevention catalyst is used for hydrogenation dechlorination reactions, and more specifically, the carbon deposition prevention catalyst is used for the preparation of chlorotrifluoroethylene by hydrogenation dechlorination of trifluorotrichloroethane, the preparation of ethylene by hydrogenation dechlorination of 1,1,2-trichloroethylene, the preparation of pentafluoroethane by hydrogenation dechlorination of pentafluorochloroethane, the preparation of 1-chloro-tetrafluoroethane and tetrafluoroethane by hydrogenation dechlorination of 1,1-dichlorotetrafluoroethane, and the preparation of 1,1,1,4,4,4-hexafluoro-2-butene by hydrogenation dechlorination of 2,3-dichloro-1,1,1,4,4,4-hexafluoro-2-butene.
[0027] When the carbon deposition prevention catalyst described in the present invention is used for a hydrogenation dechlorination reaction, the carbon deposition prevention catalyst is reduced and activated before supplying the raw material gas to carry out the hydrogenation dechlorination reaction, and the above reduction and activation step is
[0028] This process involves placing a carbon deposition prevention catalyst in a reactor and activating it by reducing it with hydrogen, where the volume space velocity of hydrogen is 2-8 minutes. -1 The heating program has a rate of 1-3°C / min, and includes raising the temperature from room temperature to 300-400°C and maintaining a constant temperature for 1-3 hours.
[0029] Furthermore, the ratio of catalyst particle size to reactor inner diameter is 1:(6~10).
[0030] Furthermore, in this application, ammonia gas and raw material gas are supplied to the reactor simultaneously to carry out a hydrogenation and dechlorination reaction, so that the ammonia gas content matches the hydrogen chloride produced, and the molar ratio of the two is set to 1:1.
[0031] The present invention further provides a method for preparing chlorotrifluoroethylene by hydrogenation and dechlorination of trifluorotrichloroethane, and specifically includes the following:
[0032] Ammonia gas, trifluorotrichloroethane (R113), and hydrogen are simultaneously supplied to a tubular reactor to carry out a hydrogenation dechlorination reaction, with a reaction temperature of 250-350°C and a space velocity of trifluorotrichloroethane of 40-100 hours. -1 The molar ratio of R113 to hydrogen is 1:(1~3), preferably 1:(1.5~2.5), and the ammonia gas content and the generated hydrogen chloride are set to 1:1.
[0033] In the actual reaction, the ammonia gas flow rate is initially set based on the theoretical hydrogen chloride content obtained from the reaction of R113 with hydrogen, and the ammonia gas flow rate is adjusted during the reaction process by monitoring the hydrogen chloride content in the product stream.
[0034] The advantages of the present invention compared to conventional technology are mainly reflected in the following points.
[0035] 1) The three metal additives in the carbon deposition prevention catalyst of the present invention can form multifunctional catalytic active centers, achieving in-situ hydrogenation removal of carbon deposition while maintaining high dechlorination catalytic performance, preventing macroscopic carbon deposition, effectively suppressing the occurrence of carbon deposition, and improving the stability and lifespan of the catalyst.
[0036] 2) When the carbon deposition prevention catalyst of the present invention is used in a hydrogenation dechlorination reaction, supplying alkaline ammonia gas simultaneously with the raw material gas reduces the acidity of the active center, suppressing the adsorption of acidic hydrogen chloride and adsorbed chlorine onto the catalyst surface and reducing the occurrence of carbon deposition. At the same time, an appropriate amount of ammonia gas reacts with hydrogen chloride to accelerate the dechlorination reaction and increase the conversion rate. [Modes for carrying out the invention]
[0037] The embodiments listed in the present invention will be described in more detail below with reference to specific examples, but the scope of protection of the present invention is not limited to the following embodiments.
[0038] The metal active ingredient salts, metal additive I salt, metal additive II salt, sodium hydroxide, hydrochloric acid, ammonium citrate, and glycolic acid used in the examples were all obtained from Sinopharm Chemical Reagent Co., Ltd., and the activated carbon was obtained from the Aladdin Chemicals Purchasing Management Platform. The specific surface area of the activated carbon was 1100 m². 2 The pore volume is 0.7648 cc / g and the ash content is 1.5% by weight.
[0039] (Example 1) (1) Weigh 8.0 mg of PtCl2, 8.0 mg of Cu(NO3)2, and 0.08 mg of nickel nitrate, and place them in a beaker containing ammonium citrate and glycolic acid, so that the molar ratio of ammonium citrate to glycolic acid is 1:1, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:2. Next, add deionized water to prepare an immersion solution with a total volume of 5.0 mL, and stir at 50°C for 5 hours.
[0040] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 6 mL of 1 mol / L sodium hydroxide solution, stir at 50°C for 2 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 6 mL of 0.5 mol / L hydrochloric acid, stir at 20°C for 2 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon carrier.
[0041] (3) Place the treated activated carbon granular support into the immersion solution prepared in step (1), gently stir the immersion solution, and after immersion is complete, leave it to stand overnight. Dry in a nitrogen atmosphere with a nitrogen flow rate of 1 mL / min, then raise the temperature from room temperature to 220°C at a rate of 1°C / min and maintain a constant temperature for 2 hours to obtain the carbon deposition catalyst.
[0042] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:6, hydrogen is supplied and reduced to activate the catalyst, and the volume space velocity of hydrogen is 2 minutes. -1 Next, the temperature is raised from room temperature to 300°C at a rate of 1°C / minute, and the temperature is kept constant for 3 hours.
[0043] (5) After reduction and activation are complete, the volume space velocity of hydrogen is 2 minutes -1 Maintain the temperature and supply gasified trifluorotrichloroethane (R113), and the volume space velocity of R113 will be 40 hours. -1 And at the same time, ammonia gas is supplied, with a flow rate of 1.4 min -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 250°C.
[0044] In chromatographic tests after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 96.45%, and the selectivity for chlorotrifluoroethylene was 96.78%.
[0045] (Example 2) (1) Weigh 8.0 mg of PtCl₂, 16.0 mg of Co(NO₃)₂ and 0.08 mg of nickel nitrate, put them into a beaker containing ammonium citrate and glycolic acid, where the molar ratio of ammonium citrate to glycolic acid is 1:2, and the molar ratio of the total of ammonium citrate and glycolic acid to the total metal is 1:1. Next, add deionized water to prepare an immersion solution with a total volume of 6.0 mL, and stir at 20 °C for 2 hours.
[0046] (2) Add 4 g of granular activated carbon with a mesh size of 10 - 20 to a beaker containing 6 mL of 3 mol / L sodium hydroxide solution, stir at 70 °C for 4 hours, then wash with deionized water until the activated carbon becomes neutral. After that, add the activated carbon to a beaker containing 6 mL of 1 mol / L hydrochloric acid, stir at 40 °C for 4 hours, then wash with deionized water until the activated carbon becomes neutral, and dry naturally to obtain a treated activated carbon support.
[0047] (3) Put the granular activated carbon support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is completed, let it stand overnight. After drying in a nitrogen atmosphere with a nitrogen flow rate of 3 mL / min, heat from room temperature to 200 °C at a rate of 3 °C / min, and maintain a constant temperature for 3 hours to obtain a carbon deposition catalyst.
[0048] (4) Put the prepared catalyst into a tubular reactor, where the ratio of the catalyst particle size to the reactor inner diameter is 1:10, supply hydrogen, reduce and activate it, and the space velocity of hydrogen is 8 minutes -1 . Then, heat from room temperature to 400 °C at a rate of 3 °C / min and maintain a constant temperature for 3 hours.
[0049] (5) After the reduction and activation are completed, maintain the space velocity of hydrogen at 8 minutes -1 , supply gasified R113, and the space velocity of R113 is 100 hours -1 . At the same time, supply ammonia gas with a flow rate of 3.4 minutes -1 , which is consistent with the flow rate of the hydrogen chloride generated, and the reaction temperature is 350 °C.
[0050] In chromatographic tests after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 96.95%, and the selectivity for chlorotrifluoroethylene was 96.89%.
[0051] (Example 3) (1) Weigh 8.0 mg of PtCl2, 40.0 mg of Co(NO3)2, and 0.08 mg of nickel nitrate, and place them in a beaker containing ammonium citrate and glycolic acid, so that the molar ratio of ammonium citrate to glycolic acid is 1:3, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:3. Next, add deionized water to prepare an immersion solution with a total volume of 6.5 mL, and stir at 30°C for 3 hours.
[0052] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 8 mL of 5 mol / L sodium hydroxide solution, stir at 90°C for 6 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 6 mL of 3 mol / L hydrochloric acid, stir at 60°C for 6 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon support.
[0053] (3) Place the activated carbon granular support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is complete, leave it to stand overnight. Dry in a nitrogen atmosphere with a nitrogen flow rate of 5 mL / min, then raise the temperature from room temperature to 200°C at a rate of 5°C / min and maintain a constant temperature for 4 hours to obtain the carbon deposition catalyst.
[0054] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:8, hydrogen is supplied and activated by reduction, and the space velocity of hydrogen is 6 minutes. -1 Next, the temperature is raised from room temperature to 350°C at a rate of 2°C / minute, and the temperature is maintained constant for 2 hours.
[0055] (5) After reduction and activation are complete, the space velocity of hydrogen is reduced to 6 minutes. -1 Maintain the supply of gasified R113, and the space velocity of R113 will be 60 hours-1 And at the same time, ammonia gas is supplied, and the flow rate is 2.1 minutes -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 280°C.
[0056] In chromatographic tests after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 97.23%, and the selectivity for chlorotrifluoroethylene was 97.18%.
[0057] (Example 4) (1) Weigh 12.0 mg of PtCl2, 80.0 mg of Co(NO3)2, and 0.012 mg of nickel nitrate, and place them in a beaker containing ammonium citrate and glycolic acid, so that the molar ratio of ammonium citrate to glycolic acid is 1:3, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:2. Next, add deionized water to prepare an immersion solution with a total volume of 7.0 mL, and stir at 50°C for 2 hours.
[0058] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 6 mL of 4 mol / L sodium hydroxide solution, stir at 80°C for 5 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 8 mL of 1 mol / L hydrochloric acid, stir at 50°C for 3 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon support.
[0059] (3) Place the activated carbon granular support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is complete, leave it to stand overnight. Dry in a nitrogen atmosphere with a nitrogen flow rate of 7 mL / min, then raise the temperature from room temperature to 250°C at a rate of 5°C / min and maintain a constant temperature for 5 hours to obtain the carbon deposition catalyst.
[0060] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:9, hydrogen is supplied and reduced to activate the catalyst, and the space velocity of hydrogen is 8 min⁻¹ -1Next, the temperature is raised from room temperature to 320°C at a rate of 2°C / minute, and the temperature is kept constant for 2 hours.
[0061] (5) After reduction and activation are complete, the space velocity of hydrogen is reduced to 8 minutes. -1 Maintain the supply of gasified R113, and the space velocity of R113 will be 80 hours -1 And at the same time, ammonia gas is supplied, and the flow rate is 2.7 minutes -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 300°C.
[0062] In chromatographic tests after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 97.65%, and the selectivity for chlorotrifluoroethylene was 97.09%.
[0063] (Example 5) (1) Weigh 16.0 mg of PtCl2, 16.0 mg of Co(NO3)2, and 0.012 mg of nickel nitrate, and place them in a beaker containing ammonium citrate and glycolic acid, so that the molar ratio of ammonium citrate to glycolic acid is 1:2, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:3. Next, add deionized water to prepare an immersion solution with a total volume of 6.0 mL, and stir at 20°C for 5 hours.
[0064] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 9 mL of 1 mol / L sodium hydroxide solution, stir at 50°C for 2 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 9 mL of 0.5 mol / L hydrochloric acid, stir at 30°C for 3 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon support.
[0065] (3) Place the activated carbon granular support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is complete, leave it to stand overnight. Dry in a nitrogen atmosphere with a nitrogen flow rate of 10 mL / min, then raise the temperature from room temperature to 250°C at a rate of 5°C / min and maintain a constant temperature for 5 hours to obtain the carbon deposition catalyst.
[0066] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:7, hydrogen is supplied and reduced to activate the catalyst, and the space velocity of hydrogen is 4 minutes. -1 Next, the temperature is raised from room temperature to 400°C at a rate of 1°C / minute, and the temperature is maintained constant for 1 hour.
[0067] (5) After reduction and activation are complete, the space velocity of hydrogen is reduced to 4 minutes. -1 Maintain the supply of gasified R113, and the space velocity of R113 will be 70 hours -1 And at the same time, ammonia gas is supplied, and the flow rate is 2.4 minutes -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 350°C.
[0068] In chromatographic tests after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 95.22%, and the selectivity for chlorotrifluoroethylene was 97.82%.
[0069] (Example 6) (1) Weigh 8.0 mg of PtCl2, 16.0 mg of Co(NO3)2, and 0.08 mg of nickel nitrate, and place them in a beaker containing ammonium citrate and glycolic acid, so that the molar ratio of ammonium citrate to glycolic acid is 1:1, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:1. Next, add deionized water to prepare an immersion solution with a total volume of 7.0 mL, and stir at 50°C for 3 hours.
[0070] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 9 mL of 1 mol / L sodium hydroxide solution, stir at 50°C for 4 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 6 mL of 0.5 mol / L hydrochloric acid, stir at 50°C for 4 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon support.
[0071] (3) Place the activated carbon granular support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is complete, leave it to stand overnight. Dry in a nitrogen atmosphere with a nitrogen flow rate of 10 mL / min, then raise the temperature from room temperature to 220°C at a rate of 3°C / min and maintain a constant temperature for 5 hours to obtain the carbon deposition catalyst.
[0072] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:10, hydrogen is supplied and reduced to activate the catalyst, and the space velocity of hydrogen is 5 min⁻¹ -1 Next, the temperature is raised from room temperature to 400°C at a rate of 3°C / minute, and the temperature is kept constant for 3 hours.
[0073] (5) After reduction and activation are complete, the space velocity of hydrogen is reduced by 5 minutes. -1 Maintain the current and supply gasified R113, and the space velocity of R113 will be 100 hours -1 And at the same time, ammonia gas is supplied, and the flow rate is 3.4 minutes -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 330°C.
[0074] In the chromatographic test after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 96.65%, and the selectivity for chlorotrifluoroethylene was 96.21%.
[0075] (Example 7) (1) Weigh 8.0 mg of PtCl2, 16.0 mg of Co(NO3)2, and 0.08 mg of nickel nitrate, and place them in a beaker containing ammonium citrate and glycolic acid, so that the molar ratio of ammonium citrate to glycolic acid is 1:3, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:1. Next, add deionized water to prepare an immersion solution with a total volume of 5.5 mL, and stir at 30°C for 2 hours.
[0076] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 6 mL of 3 mol / L sodium hydroxide solution, stir at 80°C for 6 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 6 mL of 3 mol / L hydrochloric acid, stir at 50°C for 4 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon support.
[0077] (3) Place the activated carbon granular support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is complete, leave it to stand overnight. Dry in a nitrogen atmosphere with a nitrogen flow rate of 1 mL / min, then raise the temperature from room temperature to 200°C at a rate of 1°C / min and maintain a constant temperature for 2 hours to obtain the carbon deposition catalyst.
[0078] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:9, hydrogen is supplied and reduced to activate the catalyst, and the space velocity of hydrogen is 8 min⁻¹ -1 Next, the temperature is raised from room temperature to 300°C at a rate of 3°C / minute, and then maintained at a constant temperature for 1 hour.
[0079] (5) After reduction and activation are complete, the space velocity of hydrogen is reduced to 8 minutes. -1 Maintain the supply of gasified R113, and the space velocity of R113 will be 90 hours -1 And at the same time, ammonia gas is supplied, and the flow rate is 3.1 minutes -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 330°C.
[0080] In chromatographic tests after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 96.45%, and the selectivity for chlorotrifluoroethylene was 97.34%.
[0081] (Example 8) (1) Weigh 8.0 mg of PdCl2, 80.0 mg of Cu(NO3)2, and 0.08 mg of nickel nitrate, and place them in a beaker containing ammonium citrate and glycolic acid, so that the molar ratio of ammonium citrate to glycolic acid is 1:2, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:1. Next, add deionized water to prepare an immersion solution with a total volume of 6.0 mL, and stir at 30°C for 5 hours.
[0082] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 10 mL of 1 mol / L sodium hydroxide solution, stir at 50°C for 2 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 10 mL of 0.5 mol / L hydrochloric acid, stir at 20°C for 2 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon support.
[0083] (3) Place the activated carbon granular support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is complete, leave it to stand overnight. Dry in a nitrogen atmosphere with a nitrogen flow rate of 10 mL / min, then raise the temperature from room temperature to 250°C at a rate of 1°C / min and maintain a constant temperature for 3 hours to obtain the carbon deposition catalyst.
[0084] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:8, hydrogen is supplied and activated by reduction, and the space velocity of hydrogen is 8 minutes. -1 Next, the temperature is raised from room temperature to 380°C at a rate of 1°C / minute, and the temperature is maintained constant for 3 hours.
[0085] (5) After reduction and activation are complete, the space velocity of hydrogen is reduced to 8 minutes. -1 Maintain the supply of gasified R113, and the space velocity of R113 will be 60 hours-1 And at the same time, ammonia gas is supplied, and the flow rate is 2.1 minutes -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 350°C.
[0086] In chromatographic tests after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 98.75%, and the selectivity for chlorotrifluoroethylene was 95.87%.
[0087] (Example 9) (1) Weigh 8.0 mg of PtCl2, 16.0 mg of Co(NO3)2, and 0.08 mg of nickel nitrate, and place them in a beaker containing ammonium citrate and glycolic acid so that the molar ratio of ammonium citrate to glycolic acid is 1:2, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:2. Next, add deionized water to prepare an immersion solution with a total volume of 7.0 mL, and stir at 30°C for 3 hours.
[0088] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 12 mL of 1 mol / L sodium hydroxide solution, stir at 60°C for 4 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 6 mL of 0.5 mol / L hydrochloric acid, stir at 30°C for 4 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon carrier.
[0089] (3) Place the activated carbon granular support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is complete, leave it to stand overnight. Dry in a nitrogen atmosphere with a nitrogen flow rate of 10 mL / min, then raise the temperature from room temperature to 250°C at a rate of 1°C / min and maintain a constant temperature for 5 hours to obtain the carbon deposition catalyst.
[0090] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:10, hydrogen is supplied and reduced to activate the catalyst, and the space velocity of hydrogen is 8 minutes. -1Next, the temperature is raised from room temperature to 400°C at a rate of 2°C / minute, and the temperature is kept constant for 3 hours.
[0091] (5) After reduction and activation are complete, the space velocity of hydrogen is reduced to 8 minutes. -1 Maintain the current and supply gasified R113, and the space velocity of R113 will be 100 hours -1 And at the same time, ammonia gas is supplied, and the flow rate is 3.4 minutes -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 340°C.
[0092] In chromatographic tests after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 96.35%, and the selectivity for chlorotrifluoroethylene was 96.77%.
[0093] (Example 10) (1) Weigh 8.0 mg of PtCl2, 80.0 mg of Cu(NO3)2, and 0.08 mg of nickel nitrate, and place them in a beaker containing ammonium citrate and glycolic acid, so that the molar ratio of ammonium citrate to glycolic acid is 1:3, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:2.5. Next, add deionized water to prepare an immersion solution with a total volume of 5.5 mL, and stir at 50°C for 5 hours.
[0094] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 12 mL of 1 mol / L sodium hydroxide solution, stir at 90°C for 6 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 12 mL of 3 mol / L hydrochloric acid, stir at 60°C for 6 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon support.
[0095] (3) Place the activated carbon granular support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is complete, leave it to stand overnight. Dry in a nitrogen atmosphere with a nitrogen flow rate of 8 mL / min, then raise the temperature from room temperature to 250°C at a rate of 4°C / min and maintain a constant temperature for 3 hours to obtain the carbon deposition catalyst.
[0096] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:10, hydrogen is supplied and reduced to activate the catalyst, and the space velocity of hydrogen is 5 min⁻¹ -1 Next, the temperature is raised from room temperature to 370°C at a rate of 3°C / minute, and the temperature is kept constant for 2 hours.
[0097] (5) After reduction and activation are complete, the space velocity of hydrogen is reduced by 5 minutes. -1 Maintain the temperature and supply gasified trifluorotrichloroethane (R113), and the volume space velocity of R113 will be 80 hours. -1 And at the same time, ammonia gas is supplied, and the flow rate is 2.7 minutes -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 270°C.
[0098] In chromatographic tests after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 97.85%, and the selectivity for chlorotrifluoroethylene was 95.86%.
[0099] (Example 11) (1) Weigh 8.0 mg of PdCl2, 80.0 mg of Zn(NO3)2, and 0.08 mg of ruthenium chloride, and place them in a beaker containing ammonium citrate and glycolic acid, so that the molar ratio of ammonium citrate to glycolic acid is 1:1.5, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:3. Next, add deionized water to prepare an immersion solution with a total volume of 6.0 mL, and stir at 50°C for 5 hours.
[0100] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 10 mL of 5 mol / L sodium hydroxide solution, stir at 80°C for 3 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 12 mL of 2 mol / L hydrochloric acid, stir at 50°C for 2 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon carrier.
[0101] (3) Place the activated carbon granular support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is complete, leave it to stand overnight. Dry in a nitrogen atmosphere with a nitrogen flow rate of 5 mL / min, then raise the temperature from room temperature to 250°C at a rate of 3°C / min and maintain a constant temperature for 3 hours to obtain the carbon deposition catalyst.
[0102] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:7, hydrogen is supplied and reduced to activate the catalyst, and the space velocity of hydrogen is 4 minutes. -1 Next, the temperature is raised from room temperature to 340°C at a rate of 2°C / minute, and the temperature is kept constant for 2 hours.
[0103] (5) After reduction and activation are complete, the space velocity of hydrogen is reduced to 4 minutes. -1 Maintain the supply of gasified R113, and the space velocity of R113 will be 90 hours -1 And at the same time, ammonia gas is supplied, and the flow rate is 3.1 minutes -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 260°C.
[0104] In chromatographic tests after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 97.15%, and the selectivity for chlorotrifluoroethylene was 96.45%.
[0105] (Example 12) (1) Weigh 8.0 mg of PdCl2, 80.0 mg of Co(NO3)2, and 0.08 mg of nickel nitrate, and place them in a beaker containing ammonium citrate and glycolic acid, so that the molar ratio of ammonium citrate to glycolic acid is 1:2, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:2.5. Next, add deionized water to prepare an immersion solution with a total volume of 5.5 mL, and stir at 50°C for 5 hours.
[0106] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 10 mL of 1 mol / L sodium hydroxide solution, stir at 50°C for 5 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 12 mL of 0.5 mol / L hydrochloric acid, stir at 20°C for 6 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon carrier.
[0107] (3) Place the activated carbon granular support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is complete, leave it to stand overnight. Dry in a nitrogen atmosphere with a nitrogen flow rate of 10 mL / min, then raise the temperature from room temperature to 230°C at a rate of 5°C / min and maintain a constant temperature for 4 hours to obtain the carbon deposition catalyst.
[0108] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:7, hydrogen is supplied and activated by reduction, and the space velocity of hydrogen is 6 minutes. -1 Next, the temperature is raised from room temperature to 330°C at a rate of 3°C / minute, and then maintained at a constant temperature for 1 hour.
[0109] (5) After reduction and activation are complete, the space velocity of hydrogen is reduced to 6 minutes. -1 Maintain the current and supply gasified R113, and the space velocity of R113 will be 100 hours -1 And at the same time, ammonia gas is supplied, and the flow rate is 3.4 minutes -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 300°C.
[0110] In the chromatographic test after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 97.05%, and the selectivity for chlorotrifluoroethylene was 97.09%.
[0111] (Example 13) (1) Weigh 8.0 mg of PtCl2, 16.0 mg of Co(NO3)2, and 0.08 mg of nickel nitrate, and place them in a beaker containing ammonium citrate and glycolic acid, so that the molar ratio of ammonium citrate to glycolic acid is 1:3, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:2. Next, add deionized water to prepare an immersion solution with a total volume of 6.0 mL, and stir at 50°C for 5 hours.
[0112] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 9 mL of 1 mol / L sodium hydroxide solution, stir at 90°C for 2 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 9 mL of 0.5 mol / L hydrochloric acid, stir at 60°C for 2 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon carrier.
[0113] (3) Place the activated carbon granular support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is complete, leave it to stand overnight. Dry in a nitrogen atmosphere with a nitrogen flow rate of 10 mL / min, then raise the temperature from room temperature to 250°C at a rate of 1°C / min and maintain a constant temperature for 5 hours to obtain the carbon deposition catalyst.
[0114] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:7, hydrogen is supplied and reduced to activate the catalyst, and the space velocity of hydrogen is 5 min⁻¹ -1 Next, the temperature is raised from room temperature to 400°C at a rate of 1°C / minute, and the temperature is maintained constant for 3 hours.
[0115] (5) After reduction and activation are complete, the space velocity of hydrogen is reduced by 5 minutes. -1 Maintain the supply of gasified R113, and the space velocity of R113 will be 60 hours-1 And at the same time, ammonia gas is supplied, and the flow rate is 2.1 minutes -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 320°C.
[0116] In chromatographic tests after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 97.93%, and the selectivity for chlorotrifluoroethylene was 96.59%.
[0117] (Example 14) (1) Weigh 8.0 mg of PtCl2, 80.0 mg of Co(NO3)2, and 0.08 mg of nickel nitrate, and place them in a beaker containing ammonium citrate and glycolic acid, so that the molar ratio of ammonium citrate to glycolic acid is 1:3, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:2.5. Next, add deionized water to prepare an immersion solution with a total volume of 5.0 mL, and stir at 50°C for 5 hours.
[0118] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 7 mL of 1 mol / L sodium hydroxide solution, stir at 50°C for 5 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 8 mL of 0.5 mol / L hydrochloric acid, stir at 20°C for 5 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon carrier.
[0119] (3) Place the activated carbon granular support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is complete, leave it to stand overnight. Dry in a nitrogen atmosphere with a nitrogen flow rate of 8 mL / min, then raise the temperature from room temperature to 250°C at a rate of 5°C / min and maintain a constant temperature for 2 hours to obtain the carbon deposition catalyst.
[0120] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:10, hydrogen is supplied and reduced to activate the catalyst, and the space velocity of hydrogen is 6 minutes. -1Next, the temperature is raised from room temperature to 320°C at a rate of 1°C / minute, and the temperature is maintained constant for 3 hours.
[0121] (5) After reduction and activation are complete, the space velocity of hydrogen is reduced to 6 minutes. -1 Maintain the gasified raw material gas and supply it, and the space velocity of the raw material gas is maintained for 50 hours. -1 And at the same time, ammonia gas is supplied, and the flow rate is 1.7 minutes -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 260°C.
[0122] In the chromatographic test after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 96.90%, and the selectivity for chlorotrifluoroethylene was 96.69%.
[0123] (Example 15) (1) Weigh 8.0 mg of PtCl2, 16.0 mg of Co(NO3)2, and 0.08 mg of nickel nitrate, and place them in a beaker containing ammonium citrate and glycolic acid, so that the molar ratio of ammonium citrate to glycolic acid is 1:1, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:2. Next, add deionized water to prepare an immersion solution with a total volume of 6.5 mL, and stir at 50°C for 5 hours.
[0124] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 6 mL of 1 mol / L sodium hydroxide solution, stir at 50°C for 2 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 9 mL of 3 mol / L hydrochloric acid, stir at 20°C for 5 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon carrier.
[0125] (3) Place the activated carbon granular support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is complete, leave it to stand overnight. Dry in a nitrogen atmosphere with a nitrogen flow rate of 1 mL / min, then raise the temperature from room temperature to 250°C at a rate of 1°C / min and maintain a constant temperature for 2 hours to obtain the carbon deposition catalyst.
[0126] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:10, hydrogen is supplied and activated by reduction, and the space velocity of hydrogen is 3 minutes. -1 Next, the temperature is raised from room temperature to 380°C at a rate of 1°C / minute, and then maintained at a constant temperature for 1 hour.
[0127] (5) After reduction and activation are complete, the space velocity of hydrogen is reduced to 3 minutes. -1 Maintain the gasified raw material gas and supply it, and the space velocity of the raw material gas is maintained for 50 hours. -1 And at the same time, ammonia gas is supplied, and the flow rate is 2.7 minutes -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 310°C.
[0128] In chromatographic tests after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 96.65%, and the selectivity for chlorotrifluoroethylene was 96.45%.
[0129] (Example 16) (1) Weigh 8.0 mg of PtCl2, 16.0 mg of Co(NO3)2, and 0.08 mg of nickel nitrate, and place them in a beaker containing ammonium citrate and glycolic acid, so that the molar ratio of ammonium citrate to glycolic acid is 1:2, and the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:3. Next, add deionized water to prepare an immersion solution with a total volume of 6.0 mL, and stir at 50°C for 5 hours.
[0130] (2) Add 4 g of granular activated carbon with a mesh size of 10-20 to a beaker containing 6 mL of 1 mol / L sodium hydroxide solution, stir at 50°C for 6 hours, then wash with deionized water until the activated carbon becomes neutral, then add the activated carbon to a beaker containing 9 mL of 3 mol / L hydrochloric acid, stir at 20°C for 5 hours, then wash with deionized water until the activated carbon becomes neutral, and air dry to obtain the treated activated carbon carrier.
[0131] (3) Place the activated carbon granular support treated in step (2) into the immersion solution prepared in step (1), gently stir the immersion solution, and after the immersion is complete, leave it to stand overnight. After immersion in a nitrogen atmosphere with a nitrogen flow rate of 1 mL / min, raise the temperature from room temperature to 250°C at a rate of 5°C / min and maintain a constant temperature for 4 hours to obtain the carbon deposition catalyst.
[0132] (4) The prepared catalyst is placed in a tubular reactor, the ratio of catalyst particle size to reactor inner diameter is 1:10, hydrogen is supplied and reduced to activate the catalyst, and the space velocity of hydrogen is 6 minutes. -1 Next, the temperature is raised from room temperature to 400°C at a rate of 2°C / minute, and the temperature is kept constant for 2 hours.
[0133] (5) After reduction and activation are complete, the space velocity of hydrogen is reduced to 6 minutes. -1 Maintain this, supply the gasified raw material gas, and the space velocity of the raw material gas is 80 hours -1 And at the same time, ammonia gas is supplied, and the flow rate is 2.7 minutes -1 This corresponds to the flow rate of hydrogen chloride produced, and the reaction temperature is 330°C.
[0134] In chromatographic tests after 10 hours of stable operation, the area-normalized results were as follows: the conversion rate of R113 was 96.85%, and the selectivity for chlorotrifluoroethylene was 96.08%.
[0135] (Example 17) The procedure in this example is the same as in Example 2, with only the reaction temperature and the space velocity of the raw material gas R113 being changed. The catalyst performance under different reaction conditions was compared, and the results are shown in Table 1.
[0136] [Table 1] Note: The ratio of catalyst particle size to reactor inner diameter is 1:10, and the volume space velocity of hydrogen is 8 minutes. -1 Next, the temperature is raised from room temperature to 400°C at a rate of 3°C / min and maintained at a constant temperature for 3 hours. After reduction and activation are complete, the space velocity of hydrogen is maintained, and gasified R113 is supplied, with the flow rate of ammonia gas set to match the flow rate of hydrogen chloride being produced.
[0137] (Example 18) This example tests the lifetime experiment of Example 2, that is, detection analysis is performed on the reactants under different stable operating times of Example 2, and the results are shown in Table 2.
[0138] [Table 2]
[0139] The test method is as follows: The ratio of catalyst particle size to reactor inner diameter is 1:10, and the space velocity of hydrogen is 8 min⁻¹. -1 Next, the temperature is increased from room temperature to 400°C at a rate of 3°C / min, and the temperature is kept constant for 3 hours. After reduction and activation are complete, the space velocity of hydrogen is 8 minutes. -1 Maintain the supply of gasified R113, and ensure the volume space velocity of R113 is 100 hours -1 The ammonia gas flow rate is 3.4 minutes -1 The reaction temperature is 350°C.
[0140] (Comparative Example 1) This comparative example is compared with Example 2 to demonstrate the importance of the metal active component for catalytic performance. The preparation method is the same as in Example 2, the only difference being that the metal additive II-nickel is not added.
[0141] [Table 3]
[0142] The test method is as follows: The ratio of catalyst particle size to reactor inner diameter is 1:10, and the space velocity of hydrogen is 8 min⁻¹. -1 Next, the temperature is increased from room temperature to 400°C at a rate of 3°C / min, and the temperature is kept constant for 3 hours. After reduction and activation are complete, the space velocity of hydrogen is 8 minutes. -1 Maintain the supply of gasified R113, and ensure the volume space velocity of R113 is 100 hours -1 The ammonia gas flow rate is 3.4 minutes -1 The reaction temperature is 350°C.
[0143] (Comparative Example 2) This comparative example is compared with Example 2 to demonstrate the importance of the supported form of the metal active component for catalytic performance. The preparation method is the same as in Example 2, the only difference being the preparation of the immersion solution, in which ammonium citrate and glycolic acid are not added.
[0144] [Table 4]
[0145] (Comparative Example 3) This comparative example is compared with Example 2 to demonstrate the importance of ammonia gas for catalyst performance. The preparation method is the same as in Example 2, the only difference being that ammonia gas is not supplied during the performance test.
[0146] [Table 5]
[0147] (Comparative Example 4) This comparative example is compared with Example 2 to demonstrate the importance of metal additive II and ammonia gas for catalyst performance. The preparation method is the same as in Example 2, the only difference being that metal additive II-nickel is not added and ammonia gas is not supplied.
[0148] [Table 6]
[0149] (Comparative Example 5) This comparative example is compared with Example 2 to demonstrate the importance of the supported form of the metal active component for catalytic performance. The preparation method is the same as in Example 2, the only difference being the preparation of the immersion solution, in which only ammonium citrate is added and glycolic acid is not.
[0150] [Table 7]
[0151] (Comparative Example 6) This comparative example is compared with Example 2 to demonstrate the importance of the supported form of the metal active component for catalytic performance. The preparation method is the same as in Example 2, the only difference being the preparation of the immersion solution, in which only glycolic acid is added and ammonium citrate is not.
[0152] [Table 8]
Claims
1. A method for using a carbon deposition prevention catalyst in a hydrogenation dechlorination reaction, The aforementioned method of use involves reducing and activating the carbon deposition prevention catalyst before supplying the raw material gas to carry out the hydrogenation and dechlorination reaction, and then simultaneously supplying ammonia gas and raw material gas to a tubular reactor to carry out the hydrogenation and dechlorination reaction. The aforementioned hydrogenation-dechlorination reaction is one of the following: preparation of chlorotrifluoroethylene by hydrogenation-dechlorination of trifluorotrichloroethane; preparation of ethylene by hydrogenation-dechlorination of 1,1,2-trichloroethylene; preparation of pentafluoroethane by hydrogenation-dechlorination of pentafluorochloroethane; preparation of 1-chloro-tetrafluoroethane and tetrafluoroethane by hydrogenation-dechlorination of 1,1-dichlorotetrafluoroethane; or preparation of 1,1,1,4,4,4-hexafluoro-2-butene by hydrogenation-dechlorination of 2,3-dichloro-1,1,1,4,4,4-hexafluoro-2-butene. The catalyst is composed of activated carbon, a metal active component, metal additive I, and metal additive II, wherein the metal active component is platinum or palladium, metal additive I is zinc, copper, or cobalt, and metal additive II is ruthenium or nickel, each type of metal component contains only one type of metal, the mass content of the metal active component in the activated carbon is 0.2 to 2.0%, and the mass ratio of the metal active component, metal additive I, and metal additive II is 1:(1 to 10):(0.01 to 0.001). The method for preparing the carbon deposition prevention catalyst is as follows: A1. A step of performing activated carbon treatment, The process involves immersing the activated carbon in a 1-5 mol / L sodium hydroxide solution at 50-90°C for 2-6 hours, then rinsing with water until neutral, and finally immersing the activated carbon in a 0.5-3 mol / L hydrochloric acid solution at 20-60°C for 2-6 hours, then rinsing with water until neutral, with the ratio of activated carbon to sodium hydroxide solution / hydrochloric acid being 1:1.5-5.0 (g / mL). A2. A step of preparing an immersion solution, The process involves weighing the metal active component salt, metal additive I salt, and metal additive II salt, and uniformly mixing them in an aqueous solution of ammonium citrate and glycolic acid to form an immersion solution. A3. The step of immersing in activated carbon, The activated carbon treated in step A1 is added to the immersion solution in step A2, stirred at 20-50°C for 2-5 hours, then left to mature for 5-12 hours, after which the activated carbon is removed and dried, and the volume of the immersion solution is 1.5-2 times the pore volume of the activated carbon. A4. A step in which catalyst synthesis is performed, The method includes the steps of roasting activated carbon supporting a metal component in an inert atmosphere, raising the temperature from room temperature to 200-600°C at a rate of 1-5°C / min, and maintaining a constant temperature for 2-5 hours to obtain a carbon deposition prevention catalyst. A method for using a carbon deposition prevention catalyst in a hydrogenation dechlorination reaction, characterized by the following features.
2. A method for using a carbon deposition prevention catalyst in a hydrogenation dechlorination reaction according to claim 1, characterized in that the mass content of the metal active component in the carrier is 0.2 to 1.5%.
3. A method for using a carbon deposition prevention catalyst in a hydrogenation dechlorination reaction according to claim 1 or 2, characterized in that the mass ratio of the metal active component, metal additive I, and metal additive II is 1:(1-8):(0.01-0.003).
4. A method for using a carbon deposition prevention catalyst in a hydrogenation dechlorination reaction according to claim 1, characterized in that the molar ratio of ammonium citrate to glycolic acid is 1:1 to 3, the molar ratio of the total ammonium citrate and glycolic acid to the total metal is 1:1 to 3, the gas of the inert atmosphere is nitrogen or argon, and the flow rate is 1 to 10 mL / min.
5. The step of reducing and activating the carbon deposition prevention catalyst is as follows: This process involves placing a carbon deposition prevention catalyst in a reactor and activating it by reducing it with hydrogen, where the volume space velocity of hydrogen is 2 to 8 minutes. －１ A method for using a carbon deposition prevention catalyst in a hydrogenation dechlorination reaction according to claim 1, characterized in that the heating program is 1 to 3°C / min, the temperature is raised from room temperature to 300 to 400°C, and the temperature is maintained constant for 1 to 3 hours.
6. A method for using a carbon deposition prevention catalyst in a hydrogenation dechlorination reaction according to claim 5, characterized in that the ratio of catalyst particle size to reactor inner diameter is 1:(6-10).
7. A method for using a carbon deposition prevention catalyst in a hydrogenation dechlorination reaction according to claim 6, characterized in that the ammonia gas content matches the amount of hydrogen chloride produced and the molar ratio of the two is set to 1:
1.
8. A method for preparing chlorotrifluoroethylene by hydrogenation and dechlorination of trifluorotrichloroethane, wherein ammonia gas, trifluorotrichloroethane, and hydrogen are simultaneously supplied to a tubular reactor, and a hydrogenation and dechlorination reaction is carried out at a reaction temperature of 250 to 350°C and a space velocity of trifluorotrichloroethane for 40 to 100 hours. －１ A method for using a carbon deposition prevention catalyst in a hydrogenation dechlorination reaction according to claim 1, characterized in that the molar ratio of trifluorotrichloroethane to hydrogen is 1:(1-3), and the ammonia gas content and the generated hydrogen chloride are set to 1:1.