Process for the continuous co-production of HFO 1234ze and HCFO 1233zd (E, Z)

Abstract

The present invention discloses a method for continuously co-producing HFO1234ze and HCFO1233zd (E, Z), which comprises the following steps: using a catalyst, HF and R240fa as the bottom materials, wherein the catalyst includes an amine catalyst and a co-catalyst, controlling the reaction temperature and pressure in the reactor, and then continuously introducing HF and R240fa for fluorination reaction, and continuously extracting the products containing HFO1234ze and HCFO1233zd (E, Z). By introducing the amine catalyst and the co-catalyst, the present method constructs a homogeneous near-ionic liquid system, enabling the full fusion of the organic phase and the inorganic phase, improving the reaction efficiency, having a high total product yield, having a simple and direct process route, having an advantage in industrial production cost, having the reaction products and intermediates mainly existing in the form of olefin compounds, reducing the by-products of the fluorination reaction, reducing the purification difficulty and the equipment cost, and having a continuous, stable, safe and controllable reaction process.

Description

Technical Field

[0001] The present invention relates to the technical field of the preparation of HFO1234ze and HCFO1233zd(E, Z), and particularly relates to a method for continuously co-producing HFO1234ze and HCFO1233zd(E, Z). Background Art

[0002] Although the current refrigerant and foaming markets in China are in the replacement period of the third-generation products for the second-generation products, low-carbon substances such as the fourth-generation refrigerants and blowing agents HCFO / HFOs have attracted more and more attention inside and outside the industry and the industrial chain layout has begun.

[0003] 1,3,3,3-Tetrafluoropropene (HFO1234ze) and 1-chloro-3,3,3-trifluoropropene (HCFO1233zd) are the main members of the fourth-generation fluorine-containing refrigerant HFOs series and are the main substitutes for HFCs. HCFO1233zd has two isomers, namely the Z-isomer and the E-isomer. Due to the differences in physical properties, these two isomers can be applied to commercial uses with different requirements. Because of many performance advantages such as ODP = 0 and GWP < 1, HFO1234ze is considered to be one of the new refrigerant and blowing agent varieties that can replace CFC, HCFC, and HFC in the future.

[0004] There are various methods for preparing HCFO1233zd in the prior art. For industrial-scale production, the fluorination reaction of 1,1,1,3,3-pentachloropropane (R240fa) with hydrogen fluoride is usually selected to prepare HCFO1233zd. Patent CN113480403A discloses a method for preparing HCFO1233zd by reacting a halogenated three-carbon hydrocarbon such as R240fa with anhydrous hydrogen fluoride under the catalysis of an aluminum-magnesium composite supported catalyst. Patent US6844475B1 discloses a method for continuously preparing HCFO1233zd by the liquid-phase reaction of R240fa with hydrogen fluoride under the catalysis of a Lewis acid. In this method, HCFO1233zd can be obtained with a total yield of 90% by recycling the unreacted intermediate in the gas phase. Although the above methods can obtain HCFO1233zd with high efficiency, the above methods do not involve the separation of the cis-trans isomers of HCFO1233zd, and there are also problems such as catalyst deactivation and heavy metal environmental pollution. Patent CN103189339B discloses a catalyst-free continuous production method for trans-1-chloro-3,3,3-trifluoropropene HCFO1233zd(E). This production method includes 6 main unit operations: (1) performing a fluorination reaction of R240fa with hydrogen fluoride (continuously or semi-batchwise) and simultaneously removing the by-product HCl and the product HCFO1233zd(E); (2) recycling the unreacted R240fa and HF together with the underfluorinated by-products back to (1); (3) separating and purifying the by-product HCl; (4) separating the excess HF and returning it to (1); (5) purifying the final product HCFO1233zd(E); (6) isomerizing the by-product HCFO1233zd(Z) to HCFO1233zd(E) to maximize the process yield. Although the above process can obtain HCFO1233zd(E) with a high yield, due to the complex composition of the by-products, it is impossible to obtain the equally valuable isomer HCFO1233zd(Z) by simple separation means such as distillation, and it needs to be isomerized to HCFO1233zd(E) by fluorinated chromium oxide catalysis. This process involves heavy metal catalysts, pollutes the environment, and at the same time has complex process operations, requires a lot of equipment, and has high energy consumption costs; Chinese patents CN107652160A and CN107857690A report the preparation of HCFO1233zd by combining metal halides such as TiCl4 and SnCl4 with organic bases. Due to the addition of TiCl4, SnCl4, etc., the polymerization and coking of the reactants are inevitably increased, making it difficult to scale up industrially.

[0005] In the prior art methods for preparing HFO1234ze, as described in patents US6124510A and CN1852880B, HCFO1233zd or HFC245fa can be used as raw materials for preparation. However, the prices of HCFO1233zd and HFC245fa are relatively high, and the production costs of preparing HFO1234ze from these two are too large, resulting in poor economy.

[0006] Chinese patent CN110694654A discloses a preparation method and application of a nano-level barium chloro-fluoride catalyst, which mentions the dehydrochlorination of HCFC142b by barium chloro-fluoride in a gas-solid phase reactor, but it can only be carried out under high-temperature conditions.

[0007] In view of the problems encountered in the current production technology, considering the commonalities of HFO1234ze and HCFO1233zd in production processes and raw material selection, the co-production of HFO1234ze and HCFO1233zd (Z, E) with adjustable proportions has high feasibility and great significance, which can greatly reduce the production costs of these products. Summary of the Invention

[0008] The object of the present invention is to solve the deficiencies in the above-mentioned background technology, and provide a method for continuously co-producing HFO1234ze and HCFO1233zd (E, Z) with high yield, low cost, safety, efficiency and environmental friendliness.

[0009] To achieve the above object, the technical solution provided by the present invention is:

[0010] A method for continuously co-producing HFO1234ze and HCFO1233zd (E, Z), which includes the following steps: using a catalyst, HF and R240fa as the bottom materials, the catalyst includes an amine catalyst and a co-catalyst, controlling the reaction temperature and pressure in the reactor, and then continuously introducing HF and R240fa for fluorination reaction, and continuously extracting the product containing HFO1234ze and HCFO1233zd (E, Z).

[0011] Preferably, the amine catalyst is one or a mixture of trimethylamine, triethylamine, N,N-diisopropylethylamine, tri-n-propylamine, tri-n-butylamine, and n-butylamine.

[0012] Preferably, the co-catalyst is barium chloride, barium chloro-fluoride, or barium fluoride, preferably one of barium chloride, and the content of the co-catalyst is 1-10% of the molar equivalent of the catalyst.

[0013] Preferably, the reactor is a pressure reactor, and the pressure reactor is made of materials that can withstand the corrosion of HF and HCl.

[0014] Preferably, the composition of the bottom material is as follows: the molar ratio of the catalyst, HF, and R240fa is 1:1 to 5:10 to 50.

[0015] Preferably, HF and R240fa are continuously introduced for the fluorination reaction, wherein the molar ratio of HF to R240fa is 1:1 to 10.

[0016] Preferably, the reaction temperature in the reactor is controlled to be 90 to 180 °C.

[0017] Preferably, the reaction pressure in the reactor is controlled to be 0 to 4 MPa.

[0018] Advantages of the present invention:

[0019] (1) Using R240fa as the raw material, the present invention undergoes a fluorination reaction with HF under the action of an amine catalyst and a cocatalyst to continuously co-produce HFO1234ze and HCFO1233zd (E, Z). The total yield of the products is high, and the process route is simple and direct, having a high industrial production cost advantage.

[0020] (2) By introducing an amine catalyst and a cocatalyst, the present invention constructs a homogeneous near-ionic liquid system, enabling the full integration of the organic phase and the inorganic phase and improving the reaction efficiency.

[0021] (3) Compared with the reaction system mixed with catalysts such as tin, titanium, and antimony, the amount of tar generated by the catalyst used in the present invention is significantly reduced.

[0022] (4) The reaction products and intermediates of the present invention mainly exist in the form of olefin compounds, reducing the by-products of the fluorination reaction, lowering the purification difficulty and the cost of equipment and devices. The reaction process is continuous, stable, safe, and controllable.

[0023] (5) The reaction system of the present invention has very little corrosion and can use inexpensive carbon steel materials.

[0024] (6) The present invention does not involve the use of heavy metal catalysts and is environmentally friendly. Description of the Drawings

[0025] Figure 1 is a schematic diagram of the experimental process for the method of continuously co-producing HFO1234ze and HCFO1233zd (E, Z) according to the present invention.

[0026] Figure 2 is the composition spectrum diagram after the light components of the product prepared by the method of continuously co-producing HFO1234ze and HCFO1233zd (E, Z) according to the present invention are naturally evaporated.

[0027] Figure 3 is the gas chromatographic detection and analysis chart of the sampling of the product taken in Example 2.

[0028] Figure 4 It is the gas chromatographic detection and analysis diagram of the sampling of the product withdrawn in Example 3.

[0029] Figure 5 It is the gas chromatographic detection and analysis diagram of the sampling of the product withdrawn in Example 4.

[0030] Figure 6 It is the gas chromatographic detection and analysis diagram of the sampling of the product withdrawn in Example 5.

[0031] Figure 7 It is the gas chromatographic detection and analysis diagram of the sampling of the product withdrawn in Example 6. Detailed implementation manners

[0032] To further understand the content of the present invention, the present invention will be described in detail in combination with the embodiments. The following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0033] Example 1

[0034] Reference Figure 1-2 As shown, a method for continuously co-producing HFO1234ze and HCFO1233zd(E, Z) includes the following steps: using a catalyst, HF and R240fa as the bottom materials, the catalyst includes an amine catalyst and a promoter, controlling the reaction temperature and pressure in the reactor, and then continuously introducing HF and R240fa for fluorination reaction, and continuously withdrawing the product containing HFO1234ze and HCFO1233zd(E, Z).

[0035] By introducing the amine catalyst and the promoter, an ionic liquid-like system is constructed, so that the raw materials R240fa and anhydrous hydrogen fluoride form a homogeneous system, which promotes the reaction to proceed efficiently and with high selectivity. Under the action of the amine catalyst and the promoter, the reactants alternately carry out dehydrochlorination and addition of hydrogen fluoride. As the reaction proceeds, the degree of fluorination increases and the chlorine content decreases, resulting in a decrease in the boiling point of the substance, so that it escapes from the liquid surface. The reaction products and intermediates escaping from the reaction mainly exist in the form of olefin compounds, effectively reducing the varieties of by-products and intermediates in the fluorination reaction, facilitating the separation of the next-step product, and reducing the purification difficulty of the main products HFO1234ze and HCFO1123zd(E, Z). By adjusting the valve at the outlet of the condenser material and the flow rate of the jacket water of the condenser, the pressure in the kettle and the production flow rate are controlled. The product stream leaving the reactor condenser is washed with water and alkali, then passes through a buffer bottle to a cold well for condensation and collection of the crude product. Samples are taken for gas chromatographic detection and analysis between the buffer bottle and the cold well. The collected organic crude product is mainly composed of HFO1234ze, HCFO1233zd(E) and HCFO1233zd(Z), and the proportion of the main products can be adjusted by controlling the temperature and pressure.

[0036] The reaction mainly proceeds through the following path:

[0037] Main reaction formula:

[0038]

[0039]

[0040] Main reaction process:

[0041]

[0042] Possible reaction process: (including main side reactions)

[0043]

[0044] Example 2

[0045] Reference Figure 3 As shown, in a 2-liter pressure reactor made of materials resistant to the corrosive effects of HF and HCl, after drying, 5 g of the cocatalyst barium chloride was added and sealed. After pressure testing with nitrogen, the nitrogen was discharged and the vacuum was pumped to -0.1 MPa. Then, 101 g of the amine catalyst triethylamine was drawn in using the vacuum. After that, 400 g of HF was slowly added. After cooling to room temperature, 325 g of R240fa was slowly added as the reaction bottom material. The temperature was raised to 130 °C, and the pressure in the pressure reactor was 1.35 MPa. While maintaining the reaction pressure, R240fa (108 g / h) and HF (50 g / h) were continuously introduced through two injection ports at a molar ratio of 1:5 for the reaction. The pressure in the kettle and the production flow rate were controlled by adjusting the valve at the condenser material outlet and the flow rate of the water in the condenser jacket. The production flow leaving the reactor condenser was washed with water and alkali, passed through a buffer bottle, and then condensed in a cold well to collect the crude product. Samples were taken for gas chromatography detection and analysis at the sampling point after the buffer bottle and before the cold well. The collected organic crude product mainly consisted of HFO1234ze, HCFO1233zd(E), and HCFO1233zd(Z). R240fa and HF were continuously introduced for 100 hours, and the sampling and analysis of the production samples at different time nodes were as Figure 3 shown. The catalyst in this example used the amine catalyst triethylamine and the cocatalyst barium chloride. Among them, the amine catalyst triethylamine can also be one or a mixture of trimethylamine, N,N - diisopropylethylamine, tri-n-propylamine, tri-n-butylamine, and n-butylamine. The cocatalyst can also be barium chlorofluoride, barium fluoride, preferably one of barium chloride. The content of the cocatalyst is 1 - 10% of the molar equivalent of the catalyst.

[0046] Example 3

[0047] Reference Figure 4As shown, in a 2-liter pressure reactor made of a material that can withstand the corrosion of HF and HCl, 5g of barium chloride is added after drying and then sealed. After nitrogen pressure testing, the nitrogen is discharged and vacuumed to -0.1MPa. After 146g of n-butylamine is drawn in by vacuum, 400g of HF is slowly added. After cooling to room temperature, 325g of R240fa was used as the reaction base material, and the temperature was raised to 140°C. The reactor pressure was 1.6MPa. The reaction pressure was maintained, and R240fa (108g / h) and HF (50g / h) were continuously introduced through two injection ports at a molar ratio of 1:5 for reaction. The pressure in the reactor and the amount of product flow produced were controlled by adjusting the condenser material outlet valve and the condenser jacket water flow rate. The product flow leaving the reactor condenser was washed with water and alkali, and then passed through a buffer bottle to a cold well for condensation to collect the crude product. An air bag was connected to the cold well to collect low-boiling substances. Samples were taken after the buffer bottle and before the cold well for gas chromatography analysis. The collected crude organic products were mainly HFO1234ze, HCFO1233zd (E) and HCFO1233zd (Z). R240fa and HF were continuously introduced for 100 hours, and the samples taken at different time points were analyzed as follows Figure 4 In this embodiment, R240fa (108 g / h) and HF (50 g / h) are continuously introduced through two injection ports at a molar ratio of 1:5 for reaction, which is a preferred ratio. When using the method of the present invention, the molar ratio of HF and R240fa can be selected from 1:1 to 10.

[0048] Embodiment 4

[0049] refer to Figure 5 As shown, in a 2-liter pressure reactor made of a material that can withstand the corrosion of HF and HCl, 5g of barium chloride is added after drying and then sealed. After nitrogen pressure testing, the nitrogen is discharged and vacuumed to -0.1MPa. After 429g of tri-n-propylamine is drawn in by vacuum, 1000g of HF is slowly added. After cooling to room temperature, 325g of R240fa was used as the reaction base material, and the temperature was raised to 150°C. The reactor pressure was 3.5MPa. The reaction pressure was maintained, and R240fa (162g / h) and HF (75g / h) were continuously introduced through two injection ports at a molar ratio of 1:5 for reaction. The pressure in the reactor and the amount of product flow produced were controlled by adjusting the condenser material outlet valve and the condenser jacket water flow rate. The product flow leaving the reactor condenser was washed with water and alkali, and then passed through a buffer bottle to a cold well for condensation to collect the crude product. An air bag was connected after the cold well to collect low-boiling substances. Samples were taken after the buffer bottle and before the cold well for gas chromatography analysis. The collected crude organic products were mainly HFO1234ze, HCFO1233zd (E) and HCFO1233zd (Z). R240fa and HF were continuously introduced for 100 hours, and the samples taken at different time points were analyzed as follows Figure 5As shown. In this embodiment, when 325 g of R240fa is slowly added as the reaction base material, the temperature is raised to 150 °C, and the pressure in the reaction kettle is 3.5 MPa. The temperature and pressure here are a preferred example. When using the method of the present invention, the reaction temperature in the reactor is controlled to be 90-180 °C, and the reaction pressure in the reactor is controlled to be 0-4 MPa.

[0050] Example Five

[0051] Reference Figure 6 As shown, in a 2-liter pressure reactor made of a material resistant to the corrosive effects of HF and HCl, after drying, 5 g of barium chloride is added and sealed. After pressure testing with nitrogen, the nitrogen is discharged and the vacuum is pumped to -0.1 MPa. After sucking in 202 g of triethylamine by vacuum, 1000 g of HF is slowly added. After cooling to room temperature, 500 g of R240fa is slowly added as the reaction base material, and the temperature is raised to 120 °C, and the pressure in the reaction kettle is 1.0 MPa. While maintaining the reaction pressure, R240fa (162 g / h) and HF (85 g / h) are continuously introduced through two injection ports in a molar ratio of 1:6 for reaction. The pressure in the kettle and the production flow rate are controlled by adjusting the valve at the material outlet of the condenser and the flow rate of the jacket water of the condenser. The production flow leaving the reactor condenser is washed with water and alkali, passed through a buffer bottle, and then condensed in a cold well to collect the crude product. A gas bag is connected after the cold well to collect the low-boiling substances; a sample is taken from the buffer bottle before the cold well for gas chromatography detection and analysis. The main components of the collected organic crude product are HFO1234ze, HCFO1233zd(E), and HCFO1233zd(Z). R240fa and HF are continuously introduced for 100 hours, and the sampling analysis of the production samples at different time nodes is as Figure 6 As shown. In this embodiment, the catalyst used for the base material is 202 g of triethylamine and 5 g of barium chloride, 1000 g of HF, and 500 g of R240fa, which is a preferred example. When using the method of the present invention, the molar ratio of the catalyst, HF, and R240fa is 1:1-5:10-50.

[0052] Example Six

[0053] Reference Figure 7As shown, in a 2-liter pressure reactor made of a material resistant to the corrosive effects of HF and HCl, in a 2-liter autoclave, after drying, 5 g of barium chloride was added and sealed. After pressure testing with nitrogen, the nitrogen was discharged and the vacuum was pumped to -0.1 MPa. Then, 427 g of tri-n-propylamine was drawn in by vacuum. After that, 1000 g of HF was slowly added. After cooling to room temperature, 500 g of R240fa was slowly added as the reaction bottom material. The temperature was raised to 140 °C, and the reaction kettle pressure was 2.0 MPa. While maintaining the reaction pressure, R240fa (108 g / h) and HF (50 g / h) were continuously introduced through two injection ports at a molar ratio of 1:5 for reaction. The pressure in the kettle and the production stream extraction amount were controlled by adjusting the condenser material outlet valve and the condenser jacket water flow rate. The production stream leaving the reactor condenser was washed with water and alkali, passed through a buffer bottle, and then condensed in a cold well to collect the crude product. A gas bag was connected after the cold well to collect the low-boiling substances; samples were taken for gas chromatography detection and analysis at the sampling point between the buffer bottle and the cold well. The collected organic crude product mainly consisted of HFO1234ze, HCFO1233zd(E), and HCFO1233zd(Z). R240fa and HF were continuously introduced for 100 hours, and the sampling analysis of the extracted samples at different time nodes is as Figure 7 shown. The pressure reactor in this example can be made of materials such as aluminum, carbon steel, stainless steel, Hastalloy series alloys, Inconel 600, Monel 400, and metal containers with a fluoropolymer lining.

[0054] Although the preferred embodiments of the present invention have been described above in conjunction with the embodiments, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the spirit and scope protected by the present invention and the claims. For example: considering the randomness of soil parameters, considering the randomness of the necking section length, considering different or more safety parameters. These all fall within the protection scope of the present invention.

[0055] The above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for continuously co-producing HFO1234ze and HCFO1233zd(E, Z), characterized in that, it comprises the following steps: Using a catalyst, HF and R240fa as the bottom materials, the catalyst includes an amine catalyst and a co-catalyst. Controlling the reaction temperature and pressure in the reactor, and then continuously introducing HF and R240fa for fluorination reaction, and continuously extracting the product containing HFO1234ze and HCFO1233zd(E, Z); The amine catalyst is one or a mixture of more of triethylamine, tri-n-propylamine, and n-butylamine; The co-catalyst is barium chloride, and the content of the co-catalyst is 1 to 10% of the molar equivalent of the catalyst.

2. The method for continuously co-producing HFO1234ze and HCFO1233zd(E, Z) according to claim 1, characterized in that, the reactor is a pressure reactor, and the pressure reactor is made of a material that can withstand the corrosion of HF and HCl.

3. The method for continuously co-producing HFO1234ze and HCFO1233zd(E, Z) according to claim 1, characterized in that, the composition of the bottom materials is: the molar ratio of the catalyst, HF and R240fa is 1:1 to 5:10 to 50.

4. The method for continuously co-producing HFO1234ze and HCFO1233zd(E, Z) according to claim 1, characterized in that, for the continuous introduction of HF and R240fa for fluorination reaction, the molar ratio of HF and R240fa is 1:1 to 10.

5. The method for continuously co-producing HFO1234ze and HCFO1233zd(E, Z) according to claim 1, characterized in that, controlling the reaction temperature in the reactor to be 90 to 180 °C.

6. The method for continuously co-producing HFO1234ze and HCFO1233zd(E, Z) according to claim 1, characterized in that, controlling the reaction pressure in the reactor to be 0 to 4 MPa.

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