A bimetallic oxide composite catalyst, a preparation method and application thereof
By preparing a bimetallic oxide composite catalyst with ZnO and Al, Sr, Ba, Ru, Ni, and Ca oxide co-catalysts, the problem of catalyst coking and slagging was solved, achieving low-temperature and high-efficiency hydrofluorocarbon cracking and improving the catalyst's activity and selectivity.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHEJIANG UNIV OF TECH
- Filing Date
- 2024-07-03
- Publication Date
- 2026-04-24
AI Technical Summary
Existing catalysts are prone to carbon buildup and coking during the cracking of hydrofluorocarbons and hydrochlorofluorocarbons, resulting in short service life and high reaction temperatures, which affect the activity and selectivity of the catalysts.
A bimetallic oxide composite catalyst was used to prepare ZnO and oxide co-catalysts of Al, Sr, Ba, Ru, Ni, and Ca by physical ball milling and mixing, forming a catalyst with high activity and high selectivity for catalyzing the gas-phase deHCl removal reaction of fluorochloroalkanes.
High catalytic conversion and selectivity were achieved at lower reaction temperatures, improving catalyst stability and reducing costs.
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Figure CN118976478B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of multiphase thermal catalyst technology, specifically relating to a bimetallic oxide composite catalyst, its preparation method, and its application. Background Technology
[0002] Hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs) are non-CO2 greenhouse gases with long atmospheric lifetimes and strong greenhouse effects. To reduce their environmental impact, environmentally friendly fluorinated olefins (HFOs) can be generated through resource conversion. 2,3,3,3-Tetrafluoropropylene (HFO1234yf) is considered the most promising alternative to 1,1,1,2-tetrafluoroethane (HFC-134a), currently the main refrigerant with a gas volatile organic compound (GWP) of 1430. In contrast, HFO-1234yf has an extremely low GWP of 4, zero ozone depletion, and similar physicochemical properties to HFC-134a. This fluorinated olefin has wide applications in refrigerants, foaming agents, and aerosols, and offers significant economic benefits. Therefore, converting hydrofluorocarbons and hydrochlorofluorocarbons into economically valuable fluorinated intermediates and fluorinated olefins and other fluorinated compounds can help to effectively utilize fluorine resources.
[0003] Currently, a common method involves using metal compounds as catalysts to decompose hydrofluorocarbons and hydrochlorofluorocarbons to remove HF and HCl, preparing fluorinated olefins. However, due to the high bond energy of the CX bond, a high reaction temperature (300-800℃) is required, which easily leads to coking and affects the catalyst's lifespan. Therefore, developing a catalyst with anti-coking and high stability is of great significance for the successful conduct of the reaction.
[0004] For the gas-phase dehydrochlorination of chlorofluorocarbons (HCFCs) to produce fluorinated olefins (HFOs), the affinity of the main catalyst metal for chloride (Cl) significantly influences the reaction selectivity and conversion activity. ZnO exhibits a strong affinity for and selective adsorption of Cl, thus demonstrating high selectivity for the main product HFO-1234yf, but its activity and stability are relatively poor. By doping with other highly active and stable metals, a hybrid can be formed, enhancing the intermetallic interactions and achieving both high activity and high selectivity, showing promising application prospects in the selective dehydrochlorination field. Summary of the Invention
[0005] To address the aforementioned technical problems in existing technologies, the present invention aims to provide a bimetallic oxide composite catalyst, its preparation method, and its application. The catalyst of the present invention possesses advantages such as short preparation cycle, high catalytic yield, and simple preparation method. The application of the composite catalyst of the present invention in the catalytic deHClation of 1,1,1,2-tetrafluoro-2-chloropropane to 2,3,3,3-tetrafluoropropylene exhibits advantages such as relatively low reaction temperature, high catalytic conversion rate, high catalytic selectivity, good catalytic stability, and low catalyst cost.
[0006] Furthermore, the composite catalyst is a bimetallic oxide composite catalyst with ZnO as the main catalyst and an oxide of any one of the metals selected from Al, Sr, Ba, Ru, Ni, and Ca as a co-catalyst.
[0007] Furthermore, the preparation method of the bimetallic oxide composite catalyst is obtained by physical ball milling and mixing, including the following steps:
[0008] 1) Use a balance to accurately weigh different proportions of zinc source and co-catalyst precursor, then mix the different catalysts and weigh them, then pour them into a ball mill jar with a ball-to-material ratio of 10. Select ball milling steel balls and add them to the ball mill jar containing the mixture.
[0009] 2) After completing step 1), place the ball mill jar into the ball mill, lock the ball mill jar with a mechanical device, set the ball mill program, and after the program ends, take out the homogeneous mixture and put it into the muffle furnace for full calcination to obtain the bimetallic oxide composite catalyst.
[0010] Preferably, the zinc source in step 1) is one of zinc hydroxide and zinc carbonate, with zinc hydroxide being preferred.
[0011] Preferably, the catalyst precursor in step 1) is a hydroxide or carbonate of any one of the metals selected from Al, Sr, Ba, Ru, Ni, and Ca, more preferably a hydroxide of any one of the metals selected from Al, Sr, Ba, Ru, Ni, and Ca, and even more preferably a hydroxide of any one of the metals selected from Sr, Ba, Ni, and Ca.
[0012] Preferably, in step 1), the molar ratio of the metal element in the catalyst precursor to the zinc element in the zinc source is 0.1 to 2:1, preferably 0.1 to 1:1. The conversion rate gradually increases within this range and decreases after exceeding the ratio of 1.
[0013] Preferably, in step 1), the ball mill speed is set to 300 r / min and the ball milling time is 1 to 3 h.
[0014] Preferably, in step 2), the muffle furnace calcination temperature is set to 300–800°C and the calcination time is set to 3 hours, preferably 400–700°C.
[0015] The application of the aforementioned metal oxide composite catalyst in the gas-phase deHClation of fluorochloroalkanes to prepare fluoroolefins.
[0016] Further, the chlorofluoroalkane is 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb), and the fluorinated olefin is 2,3,3,3-tetrafluoropropene (HFO-1234yf); the process of applying the bimetallic oxide composite catalyst in the catalytic gas-phase deHClation reaction of chlorofluoroalkane to prepare fluorinated olefin is as follows: the catalyst is loaded into a fixed-bed reactor, and a mixed gas of N2 and chlorofluoroalkane is introduced. The feed volume ratio of N2 to chlorofluoroalkane is 1:0.5-5, preferably 1:0.5-1, and the total space velocity of the mixed gas of N2 and chlorofluoroalkane is 100-500 h⁻¹. -1 Preferably 200-400h -1 The reaction temperature is 200–700℃, preferably 400–600℃, and the reaction produces tetrafluoropropylene.
[0017] The bimetallic oxide composite catalyst of this invention, by incorporating a co-catalyst, such as an oxide of any metal selected from Al, Sr, Ba, Ru, Ni, and Ca, combines the high selectivity of ZnO with the high activity, stability, and anti-chlorination properties of metal M. This results in a bimetallic oxide composite catalyst that exhibits anti-chlorination properties and exhibits more active and stable reactions, solving the problems of carbon deposition and deactivation in activated carbon, metal oxide, and metal chloride catalysts. When applied to the catalytic deHClation of 1,1,1,2-tetrafluoro-2-chloropropane to prepare 2,3,3,3-tetrafluoropropylene, the resulting bimetallic oxide composite catalyst offers advantages such as relatively low reaction temperature, high catalytic conversion rate, high catalytic selectivity, good catalytic stability, and low catalyst cost. Attached Figure Description
[0018] Figure 1 This is a SEM image of the bimetallic oxide composite catalyst prepared in this invention.
[0019] Figure 2 This is a TEM image of the bimetallic oxide composite catalyst prepared in this invention. Detailed Implementation
[0020] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto.
[0021] Example 1
[0022] Weigh 0.05 mol Zn(OH)₂ and 0.05 mol Al(OH)₃, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0023] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0024] CF3CFClCH3→CH2=CFCF3+HCl
[0025] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 1.
[0026] Example 2
[0027] Weigh 0.05 mol Zn(OH)₂ and 0.005 mol Al(OH)₃, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0028] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0029] CF3CFClCH3→CH2=CFCF3+HCl
[0030] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 1.
[0031] Example 3
[0032] Weigh 0.05 mol Zn(OH)₂ and 0.1 mol Al(OH)₃, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0033] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0034] CF3CFClCH3→CH2=CFCF3+HCl
[0035] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 1.
[0036] Table 1: Catalytic activity and selectivity of catalysts with different Al contents for HCFC-244bb and HFO-1234yf
[0037]
[0038] Example 4
[0039] Weigh 0.05 mol Zn(OH)₂ and 0.05 mol Sr(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them to the ball mill jars containing the mixture. Place the ball mill jars in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0040] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0041] CF3CFClCH3→CH2=CFCF3+HCl
[0042] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 2.
[0043] Example 5
[0044] Weigh 0.05 mol Zn(OH)₂ and 0.005 mol Sr(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them to the ball mill jars containing the mixture. Place the ball mill jars in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0045] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0046] CF3CFClCH3→CH2=CFCF3+HCl
[0047] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 2.
[0048] Example 6
[0049] Weigh 0.05 mol Zn(OH)₂ and 0.1 mol Sr(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0050] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0051] CF3CFClCH3→CH2=CFCF3+HCl
[0052] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 2.
[0053] Table 2: Catalytic activity and selectivity of catalysts with different Sr contents for HCFC-244bb and HFO-1234yf
[0054]
[0055] Example 7
[0056] Weigh 0.05 mol Zn(OH)₂ and 0.05 mol Ba(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0057] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0058] CF3CFClCH3→CH2=CFCF3+HCl
[0059] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. After 30 hours of reaction, the evaluation results are shown in Table 3.
[0060] Example 8
[0061] Weigh 0.05 mol Zn(OH)₂ and 0.005 mol Ba(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0062] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0063] CF3CFClCH3→CH2=CFCF3+HCl
[0064] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. After 30 hours of reaction, the evaluation results are shown in Table 3.
[0065] Example 9
[0066] Weigh 0.05 mol Zn(OH)₂ and 0.1 mol Ba(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0067] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0068] CF3CFClCH3→CH2=CFCF3+HCl
[0069] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for both N2 and HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. After 30 hours of reaction, the evaluation results are shown in Table 3.
[0070] Table 3: Catalytic activity of catalysts with different Ba contents for HCFC-244bb and selectivity for HFO-1234yf
[0071]
[0072] Example 10
[0073] Weigh 0.05 mol Zn(OH)₂ and 0.05 mol Ru(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0074] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0075] CF3CFClCH3→CH2=CFCF3+HCl
[0076] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 4.
[0077] Example 11
[0078] Weigh 0.05 mol Zn(OH)₂ and 0.005 mol Ru(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0079] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0080] CF3CFClCH3→CH2=CFCF3+HCl
[0081] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 4.
[0082] Example 12
[0083] Weigh 0.05 mol Zn(OH)₂ and 0.1 mol Ru(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the bimetallic hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a metal oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0084] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0085] CF3CFClCH3→CH2=CFCF3+HCl
[0086] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 4.
[0087] Table 4: Catalytic activity of catalysts with different Ru contents for HCFC-244bb and selectivity for HFO-1234yf
[0088]
[0089] Example 13
[0090] Weigh 0.05 mol Zn(OH)₂ and 0.05 mol Ni(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0091] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0092] CF3CFClCH3→CH2=CFCF3+HCl
[0093] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 5.
[0094] Example 14
[0095] Weigh 0.05 mol Zn(OH)₂ and 0.005 mol Ni(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0096] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0097] CF3CFClCH3→CH2=CFCF3+HCl
[0098] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for both N2 and HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 5.
[0099] Example 15
[0100] Weigh 0.05 mol Zn(OH)₂ and 0.1 mol Ni(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0101] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0102] CF3CFClCH3→CH2=CFCF3+HCl
[0103] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 5.
[0104] Table 5: Catalytic activity of catalysts with different Ni contents for HCFC-244bb and selectivity for HFO-1234yf
[0105]
[0106] Example 16
[0107] Weigh 0.05 mol Zn(OH)₂ and 0.05 mol Ni(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 1 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0108] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0109] CF3CFClCH3→CH2=CFCF3+HCl
[0110] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 6.
[0111] Example 17
[0112] Weigh 0.05 mol Zn(OH)₂ and 0.05 mol Ni(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 2 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0113] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0114] CF3CFClCH3→CH2=CFCF3+HCl
[0115] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 6.
[0116] Table 6: Reactivity of Ni catalysts prepared at different ball milling times for HCFC-244bb and selectivity for HFO-1234yf
[0117]
[0118] Comparing the experimental results of implementation examples 13, 16, and 17, it can be seen that the ball milling time also has a slight effect on the catalyst-catalyzed reaction of HCFC-244bb to HFO-1234yf. Within the ball milling time range of 1 to 3 hours, the longer the time, the higher the reaction conversion rate. The preferred ball milling time is 3 hours.
[0119] Example 18
[0120] Weigh 0.05 mol Zn(OH)₂ and 0.05 mol Ni(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 1 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 4 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0121] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0122] CF3CFClCH3→CH2=CFCF3+HCl
[0123] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 7.
[0124] Example 19
[0125] Weigh 0.05 mol Zn(OH)₂ and 0.05 mol Ni(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 1 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 5 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0126] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0127] CF3CFClCH3→CH2=CFCF3+HCl
[0128] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 7.
[0129] Table 7: Reactivity of Ni catalysts prepared at different calcination times for HCFC-244bb and selectivity for HFO-1234yf
[0130]
[0131] Comparing the experimental results of implementation examples 13, 18, and 19, it can be seen that the calcination time in the muffle furnace has a slight effect on the catalyst-catalyzed reaction of HCFC-244bb to HFO-1234yf. Within the calcination time range of 3 to 5 hours, the longer the time, the lower the reaction conversion rate and selectivity. The preferred calcination time is 3 hours.
[0132] Example 20
[0133] Weigh 0.05 mol Zn(OH)₂ and 0.05 mol Ca(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them to the ball mill jars containing the mixture. Place the ball mill jars in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0134] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0135] CF3CFClCH3→CH2=CFCF3+HCl
[0136] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 8.
[0137] Example 21
[0138] Weigh 0.05 mol Zn(OH)₂ and 0.005 mol Ca(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them to the ball mill jars containing the mixture. Place the ball mill jars in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0139] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0140] CF3CFClCH3→CH2=CFCF3+HCl
[0141] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 8.
[0142] Example 22
[0143] Weigh 0.05 mol Zn(OH)₂ and 0.1 mol Ca(OH)₂, and divide each substance into two equal portions. First, take one portion of each substance, mix them, and weigh them. Then, place them in a ball mill jar. Repeat this process for the other portion. Weigh the required mass of steel balls for ball milling based on a ball-to-material ratio of 10. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jar in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide mixture, place all the metal hydroxides in a crucible and calcine them in a muffle furnace at 500 °C for 3 h to obtain a bimetallic oxide composite catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0144] The bimetallic oxide composite catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0145] CF3CFClCH3→CH2=CFCF3+HCl
[0146] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 8.
[0147] Table 8: Catalytic activity of catalysts with different Ca contents for HCFC-244bb and selectivity for HFO-1234yf
[0148]
[0149] Comparing the experimental results of Examples 1 to 22, it can be seen that when ZnO is used as the main catalyst and oxides of any one of the metals Sr, Ba, Ni, and Ca are used as co-catalysts, the selectivity of the HFO-1234yf catalytic reaction is maintained above 90% for 30 hours of continuous evaluation, and the catalyst conversion rate is also maintained at a high level, achieving good technical results.
[0150] Example 23
[0151] Weigh 0.05 mol of Zn(OH)₂ and place it in a ball mill jar. Then, based on a ball-to-material ratio of 10, weigh the required mass of steel balls for milling. Select two identical portions of steel balls and add them separately to the ball mill jar containing the mixture. Place the ball mill jars in a ball mill and set the milling program to a milling speed of 300 r / min and a milling time of 3 h. After removing the hydroxide, place it in a crucible and calcine it in a muffle furnace at 500 °C for 3 h to obtain the metal oxide catalyst. After cooling to room temperature for 3 h, press the sample into tablets and sieve using a 20–40 mesh sieve.
[0152] The metal oxide catalyst prepared above was used to catalyze the cracking of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to prepare 2,3,3,3-tetrafluoropropene (HFO-1234yf), as shown in the following reaction formula:
[0153] CF3CFClCH3→CH2=CFCF3+HCl
[0154] The reaction conditions were as follows: 2 ml of catalyst was loaded into a fixed-bed reactor; a mixture of N2 and HCFC-244bb was introduced at a flow rate of 5 ml / min for N2 and 5 ml / min for HCFC-244bb; and the total space velocity (HSV) of the N2 and HCFC-244bb mixture was 300 h⁻¹. -1 The reaction temperature was 500℃. The reaction was carried out for 30 hours, and the evaluation results are shown in Table 9.
[0155] Table 9: Catalytic activity of catalysts with different Ni contents for HCFC-244bb and selectivity for HFO-1234yf
[0156]
[0157] As can be seen from the experimental results of Implementation Example 23, when ZnO is used directly as a catalyst and the reaction is continuously evaluated for 30 hours, although the catalytic selectivity remains at a high level, the conversion rate is only 62.4%, and the catalytic effect is not ideal.
[0158] The contents described in this specification are merely an enumeration of the implementation forms of the inventive concept, and the scope of protection of this invention should not be regarded as limited to the specific forms described in the embodiments.
Claims
1. The application of a bimetallic oxide composite catalyst in the catalytic gas-phase deHCl removal of fluorochloroalkanes to prepare fluoroolefins, characterized in that, The bimetallic oxide composite catalyst is a bimetallic oxide composite catalyst with ZnO as the main catalyst and oxides of any one of the metals selected from Al, Sr, Ba, Ni, and Ca as co-catalysts; the fluorochloroalkane is 2-chloro-1,1,1,2-tetrafluoropropane and the fluoroolefin is 2,3,3,3-tetrafluoropropene. The preparation method of the bimetallic oxide composite catalyst includes the following steps: 1) Accurately weigh a certain amount of zinc source main catalyst and co-catalyst precursor, mix the two substances and pour them into a ball mill jar with a ball-to-material ratio of 10. Select ball mill steel balls and add them separately to the ball mill jar containing the mixture. 2) After completing step 1), place the ball mill jar into the ball mill, lock the ball mill jar with a mechanical device, set the ball mill program, and after the program ends, take out the homogeneous mixture and put it into the muffle furnace for full calcination to obtain the bimetallic oxide composite catalyst. The zinc source in step 1) is either zinc hydroxide or zinc carbonate; the catalyst precursor in step 1) is either a hydroxide or carbonate of any metal from Al, Sr, Ba, Ni, or Ca; the molar ratio of the metal element in the catalyst precursor to the zinc element in the zinc source is 0.1 to 1:
1.
2. The application of the bimetallic oxide composite catalyst according to claim 1 in the catalytic gas-phase deHCl removal of fluorochloroalkanes to prepare fluoroolefins, characterized in that, The process of applying the bimetallic oxide composite catalyst in the gas-phase deHClation of chlorofluorocarbons to prepare fluoroolefins is as follows: the catalyst is loaded into a fixed-bed reactor, and a mixed gas of N2 and chlorofluorocarbons is introduced. The feed volume ratio of N2 to chlorofluorocarbons is 1:0.5~5, and the total space velocity of the mixed gas of N2 and chlorofluorocarbons is 100~500 h⁻¹. -1 The reaction temperature is 200~700 ℃.
3. The application of the bimetallic oxide composite catalyst according to claim 1 in the catalytic gas-phase deHCl removal of fluorochloroalkanes to prepare fluoroolefins, characterized in that, In step 2), the ball mill speed is set to 300 r / min and the ball milling time is 1~3 h; in step 2), the muffle furnace calcination temperature is set to 300~800℃ and the calcination time is set to 3~5 h.