Catalyst composition for preparing CF3OF and application thereof

Abstract

The invention relates to the technical field of catalysts, in particular to a catalyst composition for preparing CF3OF and application of the catalyst composition. The catalyst composition comprises NaF and at least one other fluoride salt, wherein the mass percent of NaF in the catalyst composition is not lower than 10% and not higher than 90%. The catalyst composition provided by the invention can perfectly solve the problems existing in the reaction process, not only can effectively improve the conversion rate of fluorine gas, but also can reduce the occurrence of side reactions, and improves the reaction stability and the stability of the catalyst.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts, and in particular to a catalyst composition for preparing CF3OF and application thereof. Background Art

[0002] With the continuous development of fluorine-containing fine chemicals, CF3OF is increasingly widely used as a fluorine-containing intermediate. During the application process, the fluorine content in CF3OF seriously affects the next step of the reaction, so most applications require that the fluorine content in CF3OF be controlled within 1%. There is little research on the conversion rate of catalytic reactions in existing domestic and foreign reaction systems, and there are problems such as unstable reaction quality during the application process. In view of this, the present invention is specially proposed. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a catalyst composition for preparing CF3OF and application thereof.

[0004] Specifically, the technical solution provided by the present invention is as follows: In a first aspect, the present invention provides a catalyst composition for preparing CF3OF, wherein the catalyst composition comprises NaF and at least one other fluoride salt, wherein the mass percentage of NaF in the catalyst composition is not less than 10% and not more than 90%.

[0005] Preferably, the at least one other fluoride salt is selected from at least one of CsF, LiF and CaF2.

[0006] Preferably, the catalyst composition is in the form of pellets or powder.

[0007] Further preferably, the catalyst composition includes 40%-60% CaF2, 10%-40% NaF, and also includes 10%-40% CsF or one or more other rare metal fluoride salts.

[0008] Preferably, the catalyst composition comprises 50%±5% CaF2, 30%±5% NaF, and further comprises 20%±5% CsF.

[0009] In another embodiment, the catalyst composition includes 10%-90% of NaF and also includes 10%-90% of CsF or one or more other rare metal fluoride salts.

[0010] Preferably, the catalyst composition includes 50%±5% NaF and also includes 50%±5% CsF.

[0011] In a second aspect, the present invention provides use of the catalyst composition in the preparation of CF3OF.

[0012] Preferably, the present invention uses the catalyst composition for pellet catalysis.

[0013] Preferably, the catalytic temperature is 120-150° C., the residence time is 3-6 min, and the reaction pressure is 100 kPa-500 kPa.

[0014] In another preferred embodiment, the present invention uses the catalyst composition for powder catalysis.

[0015] Preferably, the catalytic temperature is 80-150° C., the residence time is 3-6 min, and the reaction pressure is 800 kpa-1000 kpa.

[0016] Beneficial effects: The present invention provides a catalyst composition for preparing CF3OF and its application, wherein the catalyst composition comprises NaF and at least one other fluoride salt, wherein the mass percentage of NaF in the catalyst composition is not less than 10% and not more than 90%. The catalyst composition provided by the present invention can perfectly solve the problems existing in the reaction process, can not only effectively improve the conversion rate of fluorine gas, but also can reduce the occurrence of side reactions, and improve the stability of the reaction and the stability of the catalyst. DETAILED DESCRIPTION

[0017] The present invention provides a catalyst composition for preparing CF3OF and application thereof.

[0018] The catalyst composition provided by the present invention comprises NaF and at least one other fluoride salt, wherein the mass percentage of NaF in the catalyst composition is not less than 10% and not more than 90%. Preferably, the mass percentage of NaF in the catalyst composition is not less than 20% and not more than 80%. More preferably, the mass percentage of NaF in the catalyst composition is not less than 30% and not more than 70%.

[0019] In the present invention, the other at least one fluoride salt is preferably at least one selected from CsF, LiF and CaF2.

[0020] In the present invention, the catalyst composition may be in the form of pellets or powder.

[0021] The preliminary study of the present invention shows that in the process of preparing CF3OF, when only NaF is used as a catalyst, only pellet catalysis can be used. The conversion effect in this case is acceptable, and the conversion rate can reach more than 97%, but the stability is poor, and it is easy to pulverize and block the reactor during application. When only CsF is used as a catalyst, the reaction effect is slightly better than NaF, and the conversion rate can reach more than 99%, but it can only be applied to fluidized beds for powder catalysis, the reactor structure is complex, and there are many impurities. The present invention uses a composition of NaF and at least one other fluoride salt as a mixed catalyst for preparing CF3OF, and the conversion effect has been significantly improved. Not only the conversion rate is improved, but it is also suitable for pellet catalysis and powder catalysis. Multiple methods, broaden the application scenarios of the catalyst and simplify the reaction structure.

[0022] Further preferably, the catalyst composition of the present invention includes 40% to 60% CaF2, 10%-40% NaF, and 10%-40% CsF or other one or more rare metal fluoride salts. Among them, the mass percentage content of CaF2 is preferably 45%-55%, more preferably 50%. The mass percentage content of NaF is preferably 25%-35%, more preferably 30%. The mass percentage content of CsF or other one or more rare metal fluoride salts is preferably 15%-25%, more preferably 20%. At this time, the catalyst composition is particularly suitable for pellet catalytic reaction, with a conversion rate of more than 99%, a fluorine content of less than 1%, a product purity of 85%-92%, and an impurity content of 7%-14%.

[0023] Another preferred embodiment is that the catalyst composition of the present invention includes 10%-90% NaF and 10%-90% CsF or other one or more rare metal fluoride salts. Among them, the mass percentage content of NaF is preferably 45%-55%, more preferably 50%. The mass percentage content of CsF or other one or more rare metal fluoride salts is preferably 45%-55%, more preferably 50%. At this time, the catalyst composition is particularly suitable for powder catalytic reaction, with a conversion rate of more than 99%, a fluorine content of less than 1%, a product purity of 85%-94%, and an impurity content of 5%-14%.

[0024] The present invention does not particularly limit the sources of the aforementioned raw material components, and any conventional commercial source in the art may be used.

[0025] Based on the characteristics of the above-mentioned catalyst composition, the present invention also provides the use of the catalyst composition in the preparation of CF3OF. Preferably, when the catalyst composition is used for pellet catalysis, the catalytic temperature is 120-150°C, the residence time is 3-6 min, and the reaction pressure is 100 kPa-500 kPa. Preferably, when the catalyst composition is used for powder catalysis, the catalytic temperature is 80-150°C, the residence time is 3-6 min, and the reaction pressure is 800 kPa-1000 kPa.

[0026] In summary, the present invention provides a high-efficiency mixed catalyst suitable for preparing CF3OF, including NaF, and also including one or more fluoride salts such as CaF2, CsF, and LiF. The catalytic form can be granulated into pellets to catalyze the reaction in the form of a fixed bed, or it can be catalyzed in the form of a powdered sulfide bed. When a pelletized catalytic process is adopted, the pelletized catalyst is preferably granulated with 50% ± 5% CaF2, 10% ~ 40% NaF, and 10% ~ 40% CsF or other one or more rare metal fluoride salts to form a pelletized fixed bed catalyst. When a powdered catalytic process is adopted, the powdered catalyst is preferably 45% ~ 55% NaF, and 45% ~ 55% CsF or other one or more rare metal fluoride salts are added. The conversion rate of fluorine gas in the uncatalyzed preparation of CF3OF reaction can only reach about 95% at most, and in order to exclude the fluorine gas in CF3OF, 15% ~ 20% of CF3OF needs to be wasted to purify the fluorine gas in CF3OF to less than 1%. A single fluoride salt such as NaF or CsF as a catalyst can also increase the conversion rate of fluorine gas to 97% to 99%, but the amount of other by-products will increase accordingly. The catalyst composition provided by the present invention can effectively improve the reaction stability and equipment stability, broaden the application scenarios of the catalyst, and improve the production efficiency and utilization rate of CF3OF; it can not only well improve the fluorine gas conversion rate, but also reduce the generation of by-products and improve the product purity.

[0027] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] The endpoints and any values ​​of the ranges disclosed in this specification are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0029] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "specific implementations", or "some specific implementations" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0030] In the examples provided in this specification, if no specific techniques or conditions are specified, the techniques or conditions described in the literature in this field or the product instructions are used. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased through regular channels.

[0031] Example 1 This embodiment provides a catalyst composition for preparing CF3OF, and the formula thereof is as follows by mass percentage: 50wt% CaF2, 30% NaF, and 20% CsF.

[0032] This embodiment provides a method for preparing the above-mentioned catalyst composition, comprising the steps of mixing the above-mentioned catalyst composition with a hydrofluoric acid aqueous solution, wherein the molar ratio of the composition to the hydrofluoric acid is 2:1, and the molar ratio of water to the composition is 2:1, and fully stirring the above-mentioned mixture to fully mix the catalyst composition and the hydrofluoric acid solution; placing the above-mentioned mixture for 4 hours, and then molding the above-mentioned mixture into granules, wherein the granules are cylindrical granules with a length of 5 cm and a diameter of 1 cm, and after granulation, 90% of the water is naturally volatilized by drying, and then calcining is performed, and the calcination is performed at a temperature of 600° C. for 12 hours to allow the water and hydrogen fluoride in the mixture to escape, and then a granular filler with a high contact surface is formed.

[0033] Example 2 This embodiment provides a catalyst composition for preparing CF3OF, and the formula thereof is as follows by mass percentage: 40wt% CaF2, 35% NaF, and 25% CsF.

[0034] This embodiment provides a method for preparing the above-mentioned catalyst composition, comprising the steps of mixing the above-mentioned catalyst composition with a hydrofluoric acid aqueous solution, wherein the molar ratio of the composition to the hydrofluoric acid is 2:1, and the molar ratio of water to the composition is 3:1, and fully stirring the above-mentioned mixture to fully mix the catalyst composition and the hydrofluoric acid solution; placing the above-mentioned mixture for 4 hours, and then molding the above-mentioned mixture into granules, wherein the granules are cylindrical granules with a length of 3 cm and a diameter of 1.5 cm, and after granulation, 90% of the water is naturally evaporated by drying, and then calcining is performed, and the calcination is performed at a temperature of 500° C. for 20 hours to allow the water and hydrogen fluoride in the mixture to escape, and then a granular filler with a high contact surface is formed.

[0035] Example 3 This embodiment provides a catalyst composition for preparing CF3OF, and the formula thereof is as follows by mass percentage: 60wt% CaF2, 25% NaF, and 15% CsF.

[0036] This embodiment provides a method for preparing the above-mentioned catalyst composition, comprising the steps of mixing the above-mentioned catalyst composition with a hydrofluoric acid aqueous solution, wherein the molar ratio of the composition to the hydrofluoric acid is 2:1, and the molar ratio of water to the composition is 4:1, and fully stirring the above-mentioned mixture to fully mix the catalyst composition and the hydrofluoric acid solution; placing the above-mentioned mixture for 4 hours, and then molding the above-mentioned mixture into granules, wherein the granules are cylindrical granules with a length of 5 cm and a diameter of 1 cm, and after granulation, 90% of the water is naturally evaporated by drying, and then calcining is performed, and the calcination is performed at a temperature of 500° C. for 24 hours to allow the water and hydrogen fluoride in the mixture to escape, and then a granular filler with a high contact surface is formed.

[0037] Example 4 This embodiment provides a catalyst composition for preparing CF3OF, and the formula thereof is as follows by mass percentage: 50wt% NaF, 50% CsF.

[0038] This embodiment provides a method for preparing the above-mentioned catalyst composition, the steps of which are to uniformly mix the above-mentioned catalyst composition in proportion, then place it in a vacuum oven at 150°C~250°C for 12 hours, and then load it into a catalytic reactor. The catalytic reactor needs to be replaced with refined nitrogen before the catalyst, and the catalytic reactor needs to be activated at 200°C for 2 hours before use.

[0039] Example 5 This embodiment provides a catalyst composition for preparing CF3OF, and the formula thereof is as follows by mass percentage: 45 wt% NaF, 55% CsF.

[0040] This embodiment provides a method for preparing the above-mentioned catalyst composition, the steps of which are to uniformly mix the above-mentioned catalyst composition in proportion, then place it in a vacuum oven at 150°C~250°C for 12 hours, and then load it into a catalytic reactor. The catalytic reactor needs to be replaced with refined nitrogen before the catalyst, and the catalytic reactor needs to be activated at 200°C for 2 hours before use.

[0041] Example 6 This embodiment provides a catalyst composition for preparing CF3OF, and the formula thereof is as follows by mass percentage: 55 wt% NaF and 45% CsF.

[0042] This embodiment provides a method for preparing the above-mentioned catalyst composition, the steps of which are to uniformly mix the above-mentioned catalyst composition in proportion, then place it in a vacuum oven at 150°C~250°C for 12 hours, and then load it into a catalytic reactor. The catalytic reactor needs to be replaced with refined nitrogen before the catalyst, and the catalytic reactor needs to be activated at 200°C for 2 hours before use.

[0043] Comparative Example 1 100% NaF, pellets.

[0044] The preparation method is as follows: the molar ratio of NaF to hydrofluoric acid is 2:1, the molar ratio of water to the composition is 4:1, the above mixture is fully stirred to fully mix the catalyst composition and the hydrofluoric acid solution; the above mixture is placed for 4 hours, and then the above mixture is shaped into granules, the granules are cylindrical granules with a length of 5 cm and a diameter of 1 cm, and after granulation, 90% of the water is naturally evaporated by drying, and then calcined at a temperature of 600°C for 24 hours to allow the water and hydrogen fluoride in the mixture to escape, and then a granular filler with a high contact surface is formed.

[0045] Comparative Example 2 100% CsF, powder (purchased directly, particle size is 300~500 mesh).

[0046] Experimental Example 1 Fluorine gas and CO are first passed through a first-stage fluorination reactor at a molar ratio of 1.5 to 2:1, and the reaction temperature is controlled at 85°C and the pressure is about 20 kPa, and then passed through a second-stage fluorination reactor, and the temperature is controlled at 350°C and the pressure is about 10 kPa, and then the reaction materials are collected. After the catalyst equipment is added to the second-stage fluorination reactor, the temperature of the pellet catalytic reactor in Examples 1-3 is controlled at 150°C and the pressure is about 120 kPa. The powder catalytic reactor in Examples 4-6 is a reactor with a spiral shaft, and the powder is rotated by the spiral shaft to the upper part of the reactor and falls down to contact the gas phase for catalysis, and the reaction temperature is 120°C and the pressure is about 850 kPa.

[0047] The experimental results are shown in Table 1.

[0048] Table 1 The present invention aims at the reaction characteristics and existing problems of preparing CF3OF, selects metal fluoride salts in a suitable ratio according to the catalytic characteristics and the physical characteristics of the catalyst itself, improves the fluorine gas conversion rate in industrial production, reduces the fluorine gas content in CF3OF, controls side reactions, reduces the generation of impurities, improves the stability of the reaction, simplifies the reactor structure, and improves the stability of the equipment.

[0049] As can be seen from Table 1, the catalyst composition for preparing CF3OF provided by the present invention can increase the fluorine gas conversion rate to more than 99%, control the fluorine gas content in CF3OF to less than 1%, and control other impurities to 5%~14%, thereby obtaining CF3OF with a content of 85%~94%, thereby greatly improving the application efficiency of CF3OF.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A catalyst composition for preparing CF3OF, characterized in that: The catalyst composition comprises NaF and at least one other fluoride salt, wherein the mass percentage of NaF in the catalyst composition is not less than 10% and not more than 90%.

2. The catalyst composition according to claim 1, characterized in that The at least one other fluoride salt is selected from at least one of CsF, LiF and CaF2.

3. The catalyst composition according to claim 1 or 2, characterized in that The catalyst composition is in the form of pellets or powder.

4. The catalyst composition according to any one of claims 1 to 3, characterized in that The catalyst composition includes 40% to 60% of CaF2, 10% to 40% of NaF, and 10% to 40% of CsF or one or more other rare metal fluoride salts.

5. The catalyst composition according to claim 4, characterized in that The catalyst composition includes 50%±5% CaF2, 30%±5% NaF, and also includes 20%±5% CsF.

6. The catalyst composition according to any one of claims 1 to 3, characterized in that The catalyst composition includes 10%-90% of NaF and also includes 10%-90% of CsF or one or more other rare metal fluoride salts.

7. The catalyst composition according to claim 6, characterized in that The catalyst composition includes 50%±5% of NaF and also includes 50%±5% of CsF.

8. Use of the catalyst composition according to any one of claims 1 to 7 in the preparation of CF3OF.

9. The use according to claim 8, characterized in that: Using the catalyst composition according to claim 4 or 5 for pellet catalysis; Preferably, the catalytic temperature is 120-150° C., the residence time is 3-6 min, and the reaction pressure is 100 kPa-500 kPa.

10. The use according to claim 8, characterized in that: Using the catalyst composition according to claim 6 or 7 for powder catalysis; Preferably, the catalytic temperature is 80-150° C., the residence time is 3-6 min, and the reaction pressure is 800 kpa-1000 kpa.

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