CN111499489A

CN111499489A - Isomerization method of fluorine-containing olefin

Info

Publication number: CN111499489A
Application number: CN201910104202.3A
Authority: CN
Inventors: 张迪; 刘瑶瑶; 卢朋; 李伟; 郭智恺
Original assignee: Zhejiang Chemical Industry Research Institute Co Ltd; Sinochem Lantian Co Ltd
Current assignee: Zhejiang Chemical Industry Research Institute Co Ltd; Sinochem Lantian Co Ltd
Priority date: 2019-01-30
Filing date: 2019-02-01
Publication date: 2020-08-07
Anticipated expiration: 2039-02-01
Also published as: CN111499489B

Abstract

The invention discloses a method for isomerizing fluorine-containing olefin, at least one part of a compound shown in a general formula (I) is converted into a compound shown in a general formula (II) in the presence of a catalyst,

Description

Isomerization method of fluorine-containing olefin

Technical Field

The invention belongs to the field of olefin isomerization, and particularly relates to a method for isomerizing fluorine-containing olefin.

Background

The fluorine-containing olefin compound has a double bond in its molecule, has a short atmospheric lifetime and a small global warming effect, and can be used as a substitute for Hydrochlorofluorocarbons (HCFCs) and Hydrofluorocarbons (HFCs) and as a cleaning agent, a solvent, a blowing agent, and the like.

The fluorine-containing olefin compound has two configurations, cis-isomer (cis) and trans-isomer (trans), according to the arrangement mode of substituents around a double bond in a molecule. Fluorine-containing olefins of different configurations, generally having different physical and chemical properties, are used in different fields. Therefore, from the application field, it is required to obtain fluorine-containing olefin with one configuration as much as possible, and therefore, it is required to develop a method for isomerizing fluorine-containing olefin, which can convert fluorine-containing olefin from one configuration to another configuration.

For 1,3,3, 3-tetrafluoropropene, also known as "HFO-1234 ze," there are both cis-HFO-1234ze and trans-HFO-1234ze configurations. As for the production process of 1,3,3, 3-tetrafluoropropene, Chinese CN104603089A reported a process for producing 1-chloro-3, 3, 3-trifluoro-1-propene (HCFC-1233zd) and 1,3,3, 3-tetrafluoropropene (HFO-1234ze), the reaction temperature required was 400 ℃ or more, and chlorine gas was added as a radical generator.

With respect to the preparation of compounds of different configurations of other fluoroolefin compounds, the following are reported in the prior art:

PCT patent application WO2008008351 discloses a process for the preparation of cis-1, 2,3,3, 3-pentafluoropropene (HFO-1225ye) by using a supported SbCl_wF_5-w、TiCl_xF_4-x,SnCl_yF_4-y、TaCl_zF_5-z(w and z are 0-4, and x and y are 0-3) converting trans-1, 2,3,3, 3-pentafluoropropene to cis-1, 2,3,3, 3-pentafluoropropene in an increased ratio of cis-1, 2,3,3, 3-pentafluoropropene to trans-1, 2,3,3, 3-pentafluoropropene;

PCT patent application WO2008125825 discloses a process for isomerizing (hydrohalo) fluoroalkenes by converting trans-HFO-1225ye to cis-HFO-1225ye in the presence of a catalyst selected from the group consisting of lewis acids, catalysts containing chromium oxide and at least one metal of Zn, Mg, Ni, Co, Ag, Cu, Al, Sn, Zr, or alumina.

The above-mentioned method for isomerizing a fluorine-containing olefin has problems that the reaction temperature is too high without using a catalyst, and that the catalyst activity cycle is short and the selectivity of the target product is low when using a catalyst. Therefore, there is a need for further technical improvements in the process for the isomerization of fluorine-containing olefins.

Disclosure of Invention

The invention aims to provide a method for isomerizing fluorine-containing olefin, which comprises the steps of converting fluorine-containing olefin with one configuration into fluorine-containing olefin with another configuration in the presence of a catalyst, converting at least one part of a compound shown as a general formula (I) in a raw material composition into a compound shown as a general formula (II) under the action of the catalyst, wherein:

X₁、X₂independently selected from H or F, Y is selected from F or Cl, and X₁、X₂And Y is not simultaneously F.

The inventor of the present application found in the course of research that fluorine-containing olefin compounds are easily coked on the catalyst surface due to the presence of double bonds in the molecule, resulting in covering of the active sites of the catalyst, thereby losing reactivity. According to the catalyst provided by the invention, through the synergistic action among the main catalyst, the cocatalyst and the cocatalyst can form a metal active center and an acid center on the main catalyst, and can synergistically complete a fluorine-containing olefin cis-trans isomerization process, so that the activity of the catalyst is effectively improved, side reactions are reduced, the problems are well solved, the compound shown in the general formula (I) is converted into the compound shown in the general formula (II), and the target product has high selectivity, high stability and long service life.

The invention provides a catalyst, which comprises a main catalyst, a cocatalyst and a promoter, wherein the main catalyst comprises zirconium, the cocatalyst comprises at least one selected from copper, cobalt, vanadium, nickel, tin, ruthenium, rubidium and platinum, and the promoter is at least one selected from yttrium, lanthanum, cerium, praseodymium, neodymium, calcium and magnesium.

As for the catalyst, as a preferred embodiment, the catalyst includes a main catalyst including zirconium, a co-catalyst including at least one selected from copper, cobalt, nickel, tin and platinum, and a co-catalyst selected from at least one selected from yttrium, lanthanum and magnesium.

As for the catalyst, the proportion among the main catalyst, the cocatalyst and the cocatalyst is such that when the catalyst is applied to the fluorine-containing olefin isomerization reaction, the compound represented by the general formula (I) is favorably converted into the compound represented by the general formula (II). In a preferred embodiment, the catalyst comprises a main catalyst, a cocatalyst and a cocatalyst, and the molar ratio of the main catalyst to the cocatalyst is 65-98.99: 0.01-20: 1-15. In another preferred embodiment, the catalyst comprises a main catalyst, a cocatalyst and a cocatalyst, and the molar ratio of the main catalyst to the cocatalyst is 80-96.9: 0.1-10: 3-10.

The catalyst provided by the invention can be prepared according to the methods commonly used in the field, such as an impregnation method, a precipitation method and a mechanical mixing method, so as to realize the combination of the main catalyst, the cocatalyst and the cocatalyst.

In the preparation process of the catalyst, the raw materials of the main catalyst, the cocatalyst and the cocatalyst are preferably fluorides, oxides, hydroxides, chlorides, oxychlorides, carbonates, nitrates, acetates and sulfates corresponding to the metals of the main catalyst, the cocatalyst and the cocatalyst.

As a preferred embodiment, the procatalyst is selected from the group consisting of zirconium containing compounds. As a further preferred embodiment, the zirconium-containing compound is at least one selected from the group consisting of zirconium oxychloride, zirconium carbonate, and zirconium nitrate.

As a preferred embodiment, the feedstock of the co-catalyst comprises a co-catalyst compound, preferably at least one selected from the group consisting of chlorides, carbonates, nitrates and sulfates of the co-catalyst.

As a preferred embodiment, the raw material of the promoter includes a promoter compound, preferably at least one selected from the group consisting of a chloride, a carbonate, a nitrate and a sulfate of the promoter.

As a preferred embodiment, the preparation method of the catalyst of the present invention is a precipitation-impregnation method, comprising the steps of:

(1) preparing a main catalyst compound and an auxiliary catalyst compound into a mixed solution, adding a dispersing agent and ammonia water into the mixed solution, filtering the solution to obtain a filter cake, putting the filter cake into an alcohol organic solvent, and heating for azeotropic distillation and dehydration to obtain primary powder;

(2) calcining the primary powder at the temperature of 400-800 ℃ to obtain calcined primary powder, namely zirconia containing a cocatalyst;

(3) preparing an aqueous solution containing a co-catalyst compound, putting the calcined primary powder into the aqueous solution containing the co-catalyst compound for dipping, and after dipping, molding, drying and roasting to obtain the catalyst.

In the preparation method of the catalyst provided by the invention, the used dispersing agent can be a dispersing agent commonly used in the field. As a preferred embodiment, the dispersant is at least one selected from the group consisting of polyethylene glycol, polyvinyl alcohol, phenol resin, carboxymethyl cellulose and sorbitan oleate.

The alcohol organic solvent used in the preparation method of the catalyst provided by the invention can be an alcohol organic solvent commonly used in the field. As a preferred embodiment, the alcoholic organic solvent is selected from at least one of methanol, ethanol, propanol, butanol, isopropanol, isobutanol, and t-amyl alcohol.

According to the preparation method of the catalyst provided by the invention, the dosage of the main catalyst compound, the cocatalyst compound and the cocatalyst compound can be determined according to the molar ratio among the main catalyst, the cocatalyst and the cocatalyst in the prepared catalyst.

The catalyst provided by the invention is preferably subjected to activation treatment before use. The method of activating the catalyst may be carried out according to a method of activating a catalyst commonly used in the art. By way of example, the catalyst prepared may be loaded into a reaction zone, which may be subjected to hydrogen reduction and/or fluorination pretreatment.

The isomerization reaction of the fluorine-containing olefin provided by the invention can be carried out in a gas phase.

The isomerization reaction is carried out in the presence of a catalyst. The catalyst is the catalyst.

According to the method for isomerizing the fluorine-containing olefin, when the isomerization reaction is carried out in a gas phase, the space velocity is preferably 100-1800 h^-1And further preferably 150 to 900 hours^-1。

When the isomerization reaction is carried out in a gas phase, the reaction temperature is preferably 200-500 ℃, more preferably 200-400 ℃, even more preferably 200-350 ℃, and most preferably 250-350 ℃.

As an embodiment of the present invention, X in the compound represented by the general formula (I) and the compound represented by the general formula (II)₁Is H, X₂When H, Y is Cl, the isomerization temperature is preferably set200 to 500 ℃, and further preferably 250 to 350 ℃.

As an embodiment of the present invention, X in the compound represented by the general formula (I) and the compound represented by the general formula (II)₁Is H, X₂When H, Y is F, the isomerization temperature is preferably 200 to 500 ℃ and more preferably 250 to 350 ℃.

As an embodiment of the present invention, X in the compound represented by the general formula (I) and the compound represented by the general formula (II)₁Is F, X₂When H, Y is Cl, the isomerization temperature is preferably 200 to 500 ℃, and more preferably 250 to 350 ℃.

The invention provides a method for isomerizing fluorine-containing olefin, which comprises an isomerization reaction, wherein at least one part of a compound shown in a general formula (I) in a raw material composition is converted into a compound shown in a general formula (II) under the action of a catalyst, wherein:

X₁、X₂is H, Y is F or Cl;

the catalyst comprises a main catalyst, a cocatalyst and a promoter, wherein the main catalyst comprises zirconium, the cocatalyst comprises at least one selected from copper, cobalt, vanadium, nickel, tin, ruthenium, rubidium and platinum, and the promoter is at least one selected from yttrium, lanthanum, cerium, praseodymium, neodymium, calcium and magnesium;

the isomerization reaction is carried out at the temperature of 200-00 ℃ and the airspeed of 100-1800 h^-1。

X₁、X₂is H, Y is F or Cl;

the catalyst comprises a main catalyst, a cocatalyst and a promoter, wherein the main catalyst comprises zirconium, the cocatalyst comprises at least one selected from copper, cobalt, nickel, tin and platinum, and the promoter is at least one selected from yttrium, lanthanum and magnesium;

the isomerization reaction is carried out at the temperature of 250-350 ℃, and the space velocity is 150-00 h^-1。

The invention provides a method for isomerizing fluorine-containing olefin, which is a preferred implementation method, wherein the isomerization reaction is carried out in the presence of inert gas.

The invention provides a method for isomerizing fluorine-containing olefin, which is a preferred implementation method, wherein the isomerization reaction is carried out in the presence of a gas containing oxygen. The oxygen-containing gas may be oxygen, air or a mixture of oxygen and an inert gas.

The invention provides a method for isomerizing fluorine-containing olefin, when X is in the general formulas (I) and (II)₁Is H, X₂H, Y is F, the method further comprises the following steps before the isomerization reaction:

(1) in the presence of a chromium-based catalyst, at a temperature of 200-400 ℃, CF₃Reaction of CH ═ CHCl with HF in the gas phase to give a gas phase comprising CF₃CHF and CF₃CH₂CHF₂The material (2);

(2) in the presence of an aluminum-based catalyst, at a temperature of 300-450 ℃, CF₃CH₂CHF₂Gas phase dehydrofluorination to CF₃CH＝CHF。

Compared with the prior art, the method for isomerizing the fluorine-containing olefin has the following advantages that:

(1) introducing a certain amount of low-valence cations into the position of zirconium oxide to replace zirconium ions by introducing a cocatalyst to cause great distortion of a coordination layer so as to form a structure with anion defects, wherein Zr on the surface of the structure⁴⁺Has high activityThe method can enable pi bonds in double bonds of fluorine-containing olefins to generate heterolysis so as to carry out cis-trans isomerization reaction;

(2) by introducing the co-catalyst, the co-catalyst interacts with the main catalyst to form a metal active center and an acid center in the catalyst to cooperate to complete the cis-trans isomerization process of the fluorine-containing olefin, so that the activity of the catalyst is effectively improved, the occurrence of side reactions is reduced, and the fluorine-containing olefin isomerization catalyst has better low-temperature activity and higher selectivity;

(3) when the catalyst is applied to the reaction of isomerizing transHFO-1234 ze to generate cis HFO-1234ze, the single-pass selectivity of the cis HFO-1234ze can reach more than 99.2%, the conversion rate of the transHFO-1234 ze in the circulating reaction can reach 100%, and the catalyst has no obvious deactivation phenomenon after 1000 hours of reaction.

Some of the compounds of the invention are abbreviated as follows:

HFO-1234 (E): trans-1, 3,3, 3-tetrafluoropropene (trans-HFO-1234ze)

HFO-1234 (Z): cis-1, 3,3, 3-tetrafluoropropene (cis-HFO-1234 ze).

Detailed Description

The present invention is further illustrated by the following examples, which are not intended to limit the invention to these embodiments. It will be appreciated by those skilled in the art that the present invention encompasses all alternatives, modifications and equivalents as may be included within the scope of the claims.

Example 1

280.4g ZrOCl₂·8H₂O and 30.6g Y (NO)₃)₃·6H₂Respectively preparing 1 mol/L solution from O, mixing uniformly, adding polyethylene glycol while stirring to make the mass percent of polyethylene glycol in the solution be 10%, dropwise adding 5% ammonia water solution, regulating pH value to 8.5, precipitating and aging for 3 hours, washing with deionized water, and vacuum filtering until AgNO is used₃No Cl is detected by inspection^-. Adding isobutanol into the filtered filter cake, stirring for 0.5 hour, enabling the volume ratio of the filter cake to the alcohol solution to be 1:3, and carrying out dynamic azeotropic distillation when the temperature is raised to 120 ℃ to obtain primary powder. Will be as followsThe grade powder is heated to 600 ℃ at the heating rate of 5 ℃/min in the nitrogen atmosphere, and the Y/ZrO is obtained after calcining for 2 hours₂And (3) powder. 9.4g of Cu (NO)₃)₂·3H₂Preparing solution of O, soaking Y/ZrO in the solution in equal volume₂Drying the powder under vacuum condition at 50 deg.C for 24 hr, tabletting, and adding N₂Roasting at 450 deg.c for 4 hr to obtain Cu-Y/ZrO with metal atom molar percentage of Cu, Y, Zr, 5, 8 and 87₂A catalyst.

The catalyst was charged in a tubular reactor made of Incan alloy having an inner diameter of 1/2 inches and a length of 40cm in a thickness of 5m L m, and N was introduced at 200 ℃ to the reactor₂HF is mixed gas with 10:1 flow rate of 25m L/min, the mixed gas is kept for 2 hours, then the temperature is gradually increased to 350 ℃ at the speed of 2.5 ℃/min, the mixed gas is kept for 1 hour at the temperature of 350 ℃, and N₂And (3) blowing HFO-1234(E), introducing the HFO-1234(E), wherein the flow is 75m L/min, the reaction temperature is 200-500 ℃, the pressure is 0.1MPa, washing and alkaline washing reaction products, separating to obtain organic matters, drying and removing water, and analyzing the composition of the organic matters by using gas chromatography, and the results are shown in Table 1.

Example 2

The same operation as in example 1 was conducted, except that the fluorine-containing olefin isomerization catalyst was made of Zr (NO)₃)₄·5H₂O、La(NO₃)₃·6H₂O、Co(NO₃)₃·6H₂O was prepared in terms of metal atom mole percent Co: L a: Zr 15:10:75 and the flow rate of HFO-1234(E) was changed to 25m L/min, the results are shown in Table 1.

Example 3

The same procedure as in example 1, except that the catalyst for isomerization of fluorinated olefin was prepared from ZrOCl₂·8H₂O、MgCl₂、RuCl₃Prepared according to the molar percentage of metal atoms Ru, Mg and Zr being 0.1:1:98.9, and the flow rate of HFO-1234(E) was changed to 50m L/min, and the results are shown in Table 1.

Example 4

The same procedure as in example 1, except that the catalyst for isomerization of fluorinated olefin was prepared from ZrOCl₂·8H₂O、Ce(NO₃)₃·6H₂O、Ni(NO₃)₂·6H₂O was prepared in terms of metal atom mole percent Ni Ce: Zr 1:3:96, and the flow of HFO-1234(E) was changed to 125m L/min, the results are shown in Table 1.

Example 5

The same procedure as in example 1, except that the catalyst for isomerization of fluorinated olefin was prepared from ZrOCl₂·8H₂O、CaCl₂、Cu(NO₃)₂·3H₂O was prepared in terms of metal atom mole percent Cu Ca Zr 20:15:65 and the HFO-1234(E) flow was changed to 150m L/min, the results are shown in Table 1.

Example 6

The same operation as in example 1 was conducted, except that the fluorine-containing olefin isomerization catalyst was composed of Zr (CH)₃COO)₄、Mg(CH₃COO)₂·4H₂O、RbNO₃、Co(NO₃)₃·6H₂O was prepared according to the metal atom mole percent Co: Rb: Mg: Zr 1.5:2.5:6:90, and the material was collected as in example 1 with the HFO-1234(E) flow rate changed to 25m L/min, and the results are shown in Table 1.

Example 7

The same procedure as in example 1, except that the catalyst for isomerization of fluorinated olefin was prepared from ZrOCl₂·8H₂O、La(NO₃)₃·6H₂O、SnCl₂、H₂PtCl₆Prepared according to the metal atom mole percentage of Pt, Sn, L a, Zr 0.5, 6, 93, 5m L of the catalyst is filled in a tubular reactor which is made of Incan alloy and has the inner diameter of 1/2 inches and the length of 40cm, and N is introduced at 250 DEG C₂:H₂Reducing the mixed gas with the ratio of 10:1 at the flow rate of 75m L/min for 2 hours, and carrying out N₂Purging is carried out, HFO-1234(E) is introduced, the flow rate is 75m L/min, the reaction temperature is 300 ℃, and the pressure is 0.1MPa, and the results are shown in Table 1.

Example 8

The same operation as in example 7, except that the fluorine-containing olefin isomerization catalyst was prepared from Zr (OH)₄、PrCl₃、H₂PtCl₆The alloy is prepared according to the mole percentage of metal atoms of Pt, Pr, Zr and 2.5, 5 and 92.5, and the reduction treatment condition is changed to 300 DEG C、N₂:H₂The reaction was carried out at 2:1 for 1 hour under a pressure of 0.1MPa and with HFO-1234(E) introduced at a flow rate of 75m L/min and at a reaction temperature of 300 ℃.

Example 9

The same operation as in example 7 was conducted, except that the fluorine-containing olefin isomerization catalyst was composed of Zr (CH)₃COO)₄、Mg(CH₃COO)₂·4H₂O、PtCl₂、VCl₃Prepared according to the mole percentage of metal atoms V, Pd, Mg, Zr 1,2, 10 and 87, and the reduction treatment is carried out under the conditions of 200 ℃ and N₂:H₂The reaction was carried out at a flow rate of 25m L/min and a reduction time of 4 hours under a flow rate of 75m L/min at a reaction temperature of 300 ℃ and a pressure of 0.1MPa, with HFO-1234(E) being introduced, the results being shown in Table 1.

Example 10

The same operation as in example 1 was conducted except that the Cu-Y/ZrO described in 1L was charged₂The catalyst and the reaction conditions are changed into that the reaction temperature is 300 ℃ and the space velocity is 200h^-1And the pressure is 0.3MPa, the reaction product directly enters a distillation tower for separation, unreacted HFO-1234(E) extracted from the tower top enters a reactor for continuous reaction, and the tower bottom components are subjected to deacidification, dehydration and rectification to obtain a target product HFO-1234 (Z). Sampling is carried out at the outlet of the reactor, organic matters are obtained by water washing, alkali washing and separation, the composition of the organic matters is analyzed by gas chromatography after drying and dewatering, and the result of the reaction for 1000 hours is shown in Table 2.

Comparative example 1

A tubular reactor made of Incan alloy having an inner diameter of 1/2 inches and a length of 40cm was charged with 5m L of commercially available ZrO having a purity of 99.9%₂Introducing N at 200 ℃₂HF is mixed gas with 10:1 flow rate of 25m L/min, the mixed gas is kept for 2 hours, then the temperature is gradually increased to 350 ℃ at the speed of 2.5 ℃/min, the mixed gas is kept for 1 hour at the temperature of 350 ℃, and N₂Purging to reduce temperature HFO-1234(E) was introduced at a flow rate of 75m L/min, a reaction temperature of 300 ℃ and a pressure of 0.1MPa, and the same materials were collected as in example 1, and the results are shown in Table 1.

Comparative example 2

280.4g ZrOCl₂·8H₂O and 30.6g Y (NO)₃)₃·6H₂O is respectively prepared into 1 mol/L solution and mixed evenlyAnd (3) uniformly stirring and adding polyethylene glycol to ensure that the mass percentage of the polyethylene glycol in the solution is 10%. Dropwise adding 5% ammonia water solution, adjusting pH to 8.5, precipitating, aging for 3 hr, washing with deionized water, and vacuum filtering until AgNO is used₃No Cl is detected by inspection^-. Adding isobutanol into the filtered filter cake, and stirring for 0.5 hour, wherein the volume ratio of the filter cake to the alcohol solution is 1: and 3, carrying out dynamic azeotropic distillation when the temperature is raised to 120 ℃ to obtain primary powder. Heating the primary powder to 600 ℃ at the heating rate of 5 ℃/min in the nitrogen atmosphere, and calcining for 2h to obtain Y/ZrO₂Tabletting and forming the powder to obtain 9.2 percent Y/ZrO₂A catalyst.

The catalyst was charged in a tubular reactor made of Incan alloy having an inner diameter of 1/2 inches and a length of 40cm in a thickness of 5m L m, and N was introduced at 200 ℃ to the reactor₂HF is mixed gas with 10:1 flow rate of 25m L/min, the mixed gas is kept for 2 hours, then the temperature is gradually increased to 350 ℃ at the speed of 2.5 ℃/min, the mixed gas is kept for 1 hour at the temperature of 350 ℃, and N₂Purging to reduce temperature HFO-1234(E) was introduced at a flow rate of 75m L/min, a reaction temperature of 300 ℃ and a pressure of 0.1MPa, and the same materials were collected as in example 1, and the results are shown in Table 1.

Comparative example 3

A tubular reactor made of Incan alloy having an inner diameter of 1/2 inches and a length of 40cm was charged with 5m L of commercial AlF having a purity of 99.9%₃In N at₂Roasting at 300 ℃ for 4h under protection, introducing HFO-1234(E), introducing 75m L/min at the flow rate of 300-350 ℃ and under the pressure of 0.1MPa, and collecting materials as in example 1, wherein the results are shown in Table 1.

Comparative example 4

120g of Cr (NO)₃)₃·9H₂Preparing solution of O in a concentration of 1 mol/L, dropwise adding 5% ammonia water solution, adjusting pH to 8.5, precipitating, aging for 3 hr, washing with deionized water, vacuum filtering to neutrality, drying at 110 deg.C for 16 hr, tabletting, and molding in N atmosphere₂Roasting for 4 hours at 400 ℃ in the atmosphere to obtain the chromium-based catalyst.

The catalyst was charged in a tubular reactor made of Incan alloy having an inner diameter of 1/2 inches and a length of 40cm in a thickness of 5m L m, and N was introduced at 200 ℃ to the reactor₂F is mixed gas with the ratio of 1:1, and the flow rate is 25m L/minHeld for 2 hours, then gradually heated to 350 ℃ at a rate of 2.5 ℃/min, held at 350 ℃ for 1 hour, and then N₂Purging to reduce temperature HFO-1234(E) was introduced at a flow rate of 75m L/min, a reaction temperature of 300 ℃ and a pressure of 0.1MPa, and the same materials were collected as in example 1, and the results are shown in Table 1.

Comparative example 5

Same operation as in example 10, except that AlF was charged₃The catalyst, results are shown in Table 2.

TABLE 1

TABLE 2

The above examples show that the catalyst provided by the invention has good stability when being used for isomerization reaction of fluorine-containing olefin, the catalyst has no obvious deactivation phenomenon after 1000 hours of reaction, cis-HFO-1234ze has high selectivity and few byproducts.

Claims

1. A method for isomerizing fluoroolefin, which is characterized by comprising the following steps:

the method comprises an isomerization reaction, at least one part of a compound shown in a general formula (I) in a raw material composition is converted into a compound shown in a general formula (II) under the action of a catalyst, wherein:

X₁、X₂independently selected from H or F, Y is selected from F or Cl, and X₁、X₂And Y is not simultaneously F;

the catalyst comprises a main catalyst, a cocatalyst and a promoter, wherein the main catalyst comprises zirconium, the cocatalyst comprises at least one selected from copper, cobalt, vanadium, nickel, tin, ruthenium, rubidium and platinum, and the promoter is at least one selected from yttrium, lanthanum, cerium, praseodymium, neodymium, calcium and magnesium.

2. The process for isomerization fluoroolefins according to claim 1, characterized by:

the catalyst comprises a main catalyst, a cocatalyst and a promoter, wherein the main catalyst comprises zirconium, the cocatalyst comprises at least one selected from copper, cobalt, nickel, tin and platinum, and the promoter is at least one selected from yttrium, lanthanum and magnesium.

3. The process for isomerization fluoroolefins according to claim 1, characterized by:

the catalyst comprises a main catalyst, a cocatalyst and a cocatalyst, wherein the molar ratio of the main catalyst to the cocatalyst is 65-98.99: 0.01-20: 1-15.

4. The process for isomerization fluoroolefins according to claim 3, characterized by:

the catalyst comprises a main catalyst, a cocatalyst and a cocatalyst, wherein the molar ratio of the main catalyst to the cocatalyst is 80-96.9: 0.1-10: 3-10.

5. The process for isomerization fluoroolefins according to claim 1, characterized by: the isomerization reaction is carried out in the gas phase.

6. The process for isomerization fluoroolefins according to claim 5, characterized by:

the isomerization reaction is carried out in a gas phase, and the space velocity is 100-1800 h^-1。

7. The process for isomerization fluoroolefins according to claim 6, characterized by:

the isomerization reaction is carried out in a gas phase, and the space velocity is 150-900 h^-1。

8. The process for isomerization fluoroolefins according to claim 1, characterized by:

in the general formulae (I) and (II), the X₁Is H, X₂H, Y is Cl, and the temperature of the isomerization reaction is 200-500 ℃; or

In the general formulae (I) and (II), the X₁Is H, X₂H, Y is F, and the temperature of the isomerization reaction is 200-500 ℃; or

In the general formulae (I) and (II), the X₁Is F, X₂H, Y is Cl, and the temperature of the isomerization reaction is 200-500 ℃.

9. The process for isomerization fluoroolefins according to claim 8, characterized by:

in the general formulae (I) and (II), the X₁Is H, X₂H, Y is Cl, and the temperature of the isomerization reaction is 250-350 ℃; or

In the general formulae (I) and (II), the X₁Is H, X₂H, Y is F, and the temperature of the isomerization reaction is 250-350 ℃; or

In the general formulae (I) and (II), the X₁Is F, X₂H, Y is Cl, and the temperature of the isomerization reaction is 250-350 ℃.

10. A method for isomerizing fluoroolefin, which is characterized by comprising the following steps:

X₁、X₂is H, Y is F or Cl;

the isomerization reaction is carried out at the temperature of 200-500 ℃, and the space velocity is 100-1800 h^-1。

11. The process for isomerization fluoroolefins according to claim 10, characterized by:

the isomerization reaction is carried out at the temperature of 250-350 ℃, and the space velocity is 150-900 h^-1。

12. The process for isomerization fluoroolefins according to claim 1, characterized by:

in the general formulae (I) and (II), the X₁Is H, X₂H, Y being F, further comprising the following steps before the isomerization reaction:

13. The process for isomerization fluoroolefins according to claim 1, characterized by: the isomerization reaction is carried out in the presence of an inert gas.

14. The process for isomerization fluoroolefins according to claim 1, characterized by: the isomerization reaction is carried out in the presence of a gas comprising oxygen.

15. A method for preparing the catalyst of claim 1, wherein the method is a precipitation-impregnation method comprising the steps of:

16. The process for preparing a catalyst according to claim 15, wherein:

the dispersing agent is selected from at least one of polyethylene glycol, polyvinyl alcohol, phenolic resin, carboxymethyl cellulose and sorbitan oleate;

the alcohol organic solvent is at least one selected from methanol, ethanol, propanol, butanol, isopropanol, isobutanol and tert-amyl alcohol.