A method for preparing sulfuryl fluoride from sulfuryl chloride

Abstract

The application discloses a method for preparing sulfuryl fluoride by using sulfuryl chloride as raw material. After sulfuryl chloride is gasified, the sulfuryl chloride is reacted with an amine complex of hydrogen fluoride in a pipeline reactor to obtain sulfuryl fluoride. The pipeline reactor is in a two-stage series connection, the heating temperature of the first stage is 100-350 DEG C, and the heating temperature of the second stage is 150-450 DEG C. The method can effectively improve the conversion rate and yield of the product and is easy to be industrialized.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for preparing sulfuryl fluoride, in particular a method for preparing sulfuryl fluoride using sulfuryl chloride as raw material. BACKGROUND

[0002] Sulfuryl fluoride is a fumigant gas used for controlling various pests. It is non-flammable, non-corrosive, and does not produce odor. It has strong penetrating power and can quickly penetrate various materials to effectively kill various social pests such as dry wood termites. When dispersed, it can quickly dissipate. Compared with bromomethane, it is faster, more effective and more economical in killing various pests, does not destroy the ozone layer, and belongs to green and environmentally friendly products.

[0003] Currently, there are three methods for preparing sulfuryl fluoride: 1) using sulfur trioxide to prepare trifluoroacetyl chloride, and then fluorinating to obtain sulfuryl fluoride; 2) using sulfuryl chloride as raw material, and preparing sulfuryl fluoride by catalytic fluorination; 3) using sulfur dioxide as raw material, and reacting with chlorine and hydrogen fluoride in a fixed bed reactor with a catalyst to obtain sulfuryl fluoride by gas phase chlorofluorination. The use of sulfur trioxide to prepare trifluoroacetyl chloride has greater environmental pollution and complex product post-treatment. The chlorofluorination reaction of sulfur dioxide, chlorine and hydrogen fluoride is limited in transportation, especially during major domestic events, holidays and other special time periods. Chlorine as a raw material often affects production progress. In addition, the reaction is catalyzed by activated carbon and potassium hydrogen fluoride, and carbon dioxide is generated during the catalytic reaction process and needs to be treated. The catalyst often fails and forms a lump, and the replacement of the catalyst not only affects the environment but also is difficult to operate. Therefore, using sulfuryl chloride as raw material and preparing sulfuryl fluoride by catalytic fluorination is a development direction. However, direct catalytic fluorination of sulfuryl chloride and hydrogen fluoride is violent, and if not handled properly, it can easily explode, which is dangerous and not suitable for industrial production. Moreover, the use of batch liquid phase reaction has low efficiency and difficult product separation.

[0004] Sulfuryl chloride, also known as sulfuryl chloride, has the English name sulfuryl chloride, the molecular formula SO2Cl2, and the molecular weight 134.97. It is a colorless or pale yellow liquid with a boiling point of 68-70℃. It is mainly used as a chlorinating agent or chlorosulfonating agent for the chlorination of aromatic compounds, the chlorination of carboxylic acids, and the chlorination of other various organic and inorganic compounds. It is also used to manufacture pharmaceuticals, dyes, surfactants, etc. SUMMARY

[0005] The technical problem to be solved by the present application is to provide a method for preparing sulfuryl fluoride by gas phase fluorination of amine complex of sulfuryl chloride and hydrogen fluoride. The method can effectively improve the yield and conversion rate of the product, and is suitable for large-scale production.

[0006] To solve the above technical problems, the application discloses a method for preparing thionyl fluoride from thionyl chloride as raw material, wherein the thionyl chloride is gasified and reacted with an amine complex of hydrogen fluoride in a pipeline reactor to obtain thionyl fluoride.

[0007] The pipeline reactor is in two stages in series, the first stage is heated to a temperature of 100-350 DEG C, and the second stage is heated to a temperature of 150-450 DEG C.

[0008] Further, the gasification temperature of the thionyl chloride is 80-150 DEG C.

[0009] Further, the gasification temperature of the thionyl chloride is 80-100 DEG C.

[0010] Further, the pipeline reactor is a rotating pipeline reactor.

[0011] Further, the amine complex of hydrogen fluoride contains one or more than two, each of which is complexed by several hydrogen fluoride molecules and one carbon C 1～6 organic amine molecule.

[0012] Further, the molar ratio of the thionyl chloride to the amine complex of hydrogen fluoride is 1:2-5, and the molar amount of the amine complex of hydrogen fluoride is calculated based on hydrogen fluoride.

[0013] Further, the feeding amount of the thionyl chloride gas is 1.35 kg / s.

[0014] The application utilizes the gas phase fluorination of the amine complex of thionyl chloride and hydrogen fluoride to prepare thionyl fluoride, which not only solves the transportation and source limitation of sulfur dioxide, chlorine and hydrogen fluoride, but also solves the environmental pressure of sulfur dioxide, chlorine and hydrogen fluoride, and is an energy-saving, emission-reducing, sustainable development, circular economy and environment-friendly production technology. Moreover, the technical scheme adopted by the application has the beneficial effects of good product quality, technical indexes of thionyl fluoride mass fraction of ≥99.8%, water content of ≤0.1%, pH of ≥3.5 (meeting the requirements of the enterprise standard Q / LMH001-2014 "Thionyl Fluoride" and the national standard GB / T 38211-2019 "Thionyl Fluoride"), and yield of ≥99.9%, easy storage and transportation of reaction raw materials, convenient feeding operation, raw material conversion rate of ≥99.9%, no need to treat the failed catalyst in the production process, easy industrialized production, and no pollution to the environment.

[0015] In addition, the application adopts continuous gas phase reaction, the product is easy to separate, the high purity of the product is ensured, and the application is more suitable for large scale. The heating temperature of two sections of the reactor is controlled, so that the reaction maintains high conversion rate. The generated sulfonyl fluoride enters a gas cabinet for next step refining. The byproduct hydrogen chloride is absorbed by water through a graphite pipeline to become a byproduct hydrochloric acid. The sulfonyl chloride, the hydrogen fluoride amine complex and the generated trace sulfonyl chloride fluoride which do not participate in the reaction are compressed and recovered for reuse. DETAILED DESCRIPTION

[0016] The application will be further explained in combination with examples. The following examples are only used to illustrate the application, but not used to limit the implementation range of the application.

[0017] Example 1

[0018] After sulfonyl chloride is gasified at 80 DEG C in a gas cabinet, the feeding amount at a flow rate of 13.5 kg / s (0.1 mole) enters a rotating pipeline reactor provided with 4 kg (0.2 mole of hydrogen fluoride) of hydrogen fluoride complex of triethylamine, and the reaction is carried out at 200 DEG C in a first rotating pipeline reactor. The heating temperature of a second reactor in series is controlled at 350 DEG C. The generated sulfonyl fluoride enters a gas cabinet for refining. The purity of sulfonyl fluoride is 99.88% by gas chromatography analysis, the conversion rate is 99.92%, and the product yield is 99.93%.

[0019] Example 2

[0020] After sulfonyl chloride is gasified at 100 DEG C in a gas cabinet, the feeding amount at a flow rate of 13.5 kg / s (0.1 mole) enters a rotating pipeline reactor provided with 6 kg (0.3 mole of hydrogen fluoride) of hydrogen fluoride complex of triethylamine, and the reaction is carried out at 100 DEG C in a first rotating pipeline reactor. The heating temperature of a second reactor in series is controlled at 250 DEG C. The generated sulfonyl fluoride enters a gas cabinet for refining. The purity of sulfonyl fluoride is 99.90% by gas chromatography analysis, the conversion rate is 99.92%, and the product yield is 99.92%.

[0021] Example 3

[0022] After sulfonyl chloride is gasified at 150 DEG C in a gas cabinet, the feeding amount at a flow rate of 13.5 kg / s (0.1 mole) enters a rotating pipeline reactor provided with 6 kg (0.3 mole of hydrogen fluoride) of hydrogen fluoride complex of tri-n-butylamine, and the reaction is carried out at 350 DEG C in a first rotating pipeline reactor. The heating temperature of a second reactor in series is controlled at 450 DEG C. The generated sulfonyl fluoride enters a gas cabinet for refining. The purity of sulfonyl fluoride is 99.82% by gas chromatography analysis, the conversion rate is 99.91%, and the product yield is 99.91%.

[0023] Example 4

[0024] Sulfuryl chloride was gasified at 150°C in a gas cabinet and fed at a flow rate of 13.5 kg / s (0.1 mole) into a rotating pipe reactor containing a hydrogen fluoride complex of cyclohexylamine of 10 kg (0.5 mole of hydrogen fluoride) and heated at 300°C in a first rotating pipe reactor, controlling the heating temperature of the second reactor in series at 450°C, and the sulfuryl fluoride generated in the reaction was refined in a gas cabinet, and the sulfuryl fluoride purity was 99.85% by gas chromatography analysis, the conversion rate was 99.90%, and the product yield was 99.91%.

[0025] Example 5

[0026] Sulfuryl chloride was gasified at 100°C in a gas cabinet and fed at a flow rate of 13.5 kg / s (0.1 mole) into a rotating pipe reactor containing a hydrogen fluoride complex of trimethylamine of 6 kg (0.3 mole of hydrogen fluoride) and heated at 100°C in a first rotating pipe reactor, controlling the heating temperature of the second reactor in series at 250°C, and the sulfuryl fluoride generated in the reaction was refined in a gas cabinet, and the sulfuryl fluoride purity was 99.92% by gas chromatography analysis, the conversion rate was 99.93%, and the product yield was 99.92%.

[0027] Example 6

[0028] Sulfuryl chloride was gasified at 100°C in a gas cabinet and fed at a flow rate of 13.5 kg / s (0.1 mole) into a rotating pipe reactor containing a hydrogen fluoride complex of trimethylamine and cyclohexylamine of 6 kg (0.3 mole of hydrogen fluoride) and heated at 100°C in a first rotating pipe reactor, controlling the heating temperature of the second reactor in series at 250°C, and the sulfuryl fluoride generated in the reaction was refined in a gas cabinet, and the sulfuryl fluoride purity was 99.93% by gas chromatography analysis, the conversion rate was 99.92%, and the product yield was 99.91%.

[0029] Example 7

[0030] Sulfuryl chloride was gasified at 150°C in a gas cabinet and fed at a flow rate of 13.5 kg / s (0.1 mole) into a rotating pipe reactor containing a hydrogen fluoride complex of trimethylamine and cyclohexylamine of 10 kg (0.5 mole of hydrogen fluoride) and heated at 300°C in a first rotating pipe reactor, controlling the heating temperature of the second reactor in series at 350°C, and the sulfuryl fluoride generated in the reaction was refined in a gas cabinet, and the sulfuryl fluoride purity was 99.86% by gas chromatography analysis, the conversion rate was 99.91%, and the product yield was 99.92%.

Claims

1. A process for the preparation of sulfuryl fluoride from sulfuryl chloride, characterized in that: Sulfuryl chloride is vaporized and reacted with amine complex of hydrogen fluoride in a pipe reactor to obtain sulfuryl fluoride by gas phase reaction; The pipe reactor is two-stage series connection, the first stage heating temperature is 100-350 DEG C, and the second stage heating temperature is 250-450 DEG C.

2. The process for preparing sulfuryl fluoride from sulfuryl chloride according to claim 1, characterized in that: The sulfuryl chloride vaporization temperature is 80-150 DEG C.

3. The process for preparing sulfuryl fluoride from sulfuryl chloride according to claim 2, characterized by: The sulfuryl chloride vaporization temperature is 80-100 DEG C.

4. The method of claim 1, wherein the method is characterized by: The pipe reactor is a rotary pipe reactor.

5. The method of claim 1, wherein the method is characterized by: The amine complex of hydrogen fluoride contains one or more than two, each of which is complexed by several molecules of hydrogen fluoride and one organic amine molecule of C 1～6 .

6. The process for preparing sulfuryl fluoride from sulfuryl chloride according to claim 1, characterized by: The sulfuryl chloride and amine complex of hydrogen fluoride are fed in a molar ratio of 1:2-5, and the molar amount of the amine complex of hydrogen fluoride is calculated based on hydrogen fluoride.

7. The method of claim 1, wherein the method is characterized by: The sulfuryl chloride gas feeding amount is 1.35 kg / s.