SU1685929A1 - Method for obtaining alkylulfochlorides - Google Patents

Abstract

The invention relates to sulfur-containing compounds and, in particular, to the preparation of alkylsulfonyl chlorides, which can be used in the synthesis of surfactants, additives. The purpose of the invention is to increase the productivity of the process and improve the quality of the target products. The method involves the interaction of Cs-C1B - n-hydrocarbons with a gaseous mixture of chlorine and sulfur dioxide in the presence of a initiating source of radiation. Iodine in the amount of 0.0005- 0.00005 wt.% Is introduced into the hydrocarbon feedstock. 2 tab.

Description

The invention relates to an improved process for the preparation of alkylsulfonyl chlorides used as an intermediate in the synthesis of surfactants, additives.

The closest technical solution to the invention is a photochemical initiation method consisting in the sulfochlorination of hydrocarbons under ultraviolet irradiation of the reaction mass, the source of which is a quartz mercury lamp.

However, the known method has the following disadvantages. In the course of the sulfochloration process, side reactions take place to varying degrees, leading to the formation of less active di- and polysulfochlorides, as well as chlorinated paraffins. The content of sulfochlorides in the resulting reaction mass is 22-28%, which corresponds to the content of sulfochlorine 2.6-3.4 wt.%. The ratio of monosulfonic and

disubstituted products (70-75): (). An increase in the degree of conversion leads to a decrease in the yield of monosulfonyl chlorides.

The purpose of the invention is to increase the productivity of the process and improve the quality of the target products.

The sulfochlorination of Cn-Cis n-hydrocarbons is carried out by exposing them1 to a gaseous mixture — chlorine and sulfur dioxide — under UV irradiation in the presence of iodine dissolved in a hydrocarbon feedstock. Introduction of iodine and carrying out sulfochlorination in its presence allows increasing the yield of alkyl sulfochlorides with a simultaneous increase in the degree of conversion of hydrocarbons.

The test of the proposed method was carried out in laboratory conditions at an installation consisting of a column-type reactor equipped with a bubbler for gas distribution, an integrated refrigerator to remove the heat of reaction, with a thermometer. The irradiation of the reaction mass produced

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but a quartz mercury lamp outside the reaction zone.

The obtained experimental data are presented in table. 12.

Example 1. Charged to the reactor 145 g of hydrocarbons fraction Cc-Cie. When the initiation source is turned on, chlorine and sulfur dioxide are supplied in an amount of 39 g / h each, which corresponds to a molar ratio of 1: 1.1, respectively. The process is conducted at 20-23 ° C for 20 minutes. At the end of the sulfochlorination operation, acidic impurities are removed from the resulting mass by stripping with air, after which it determines: the total chlorine content is 3.9 wt.%, The hydrolyzable (sulfochloride) content is 3.15 wt.%, The ratio between mono- and disulfochlorides - 72:28. The conversion of hydrocarbons calculated on the basis of these data is 15.2%, the yield of monosubstituted sulfochlorides is 75.1%.

EXAMPLE 2 The feedstock, the gaseous components are fed in analogously to Example 1, but the synthesis time is increased to 33 minutes. Sulfonyl chloride is obtained with the following indicators: total chlorine content is 6.15 wt.%, Hydrolyzable is 4.6 wt.%, The ratio of monosulfonyl chloride and disubstituted products is 62.3: 37.7. Conversion of hydrocarbons with the indicated composition sulfochloride 23.2%, yield of monosulfonyl chloride 66.4%.

Example 3. Charged to the reactor 145 g of hydrocarbon feedstock containing 0.00022 (0.00015 wt.%) Dissolved iodine. When feeding chlorine and sulfur dioxide at 39 g / h, the process takes 20 minutes. Upon completion of the operation and stripping of acid sulfide sulfochloride in it, the following is determined: the content of total chlorine is 4.0 May. %, hydrolyzable chlorine - 3.75 wt.%, the ratio of monosulfonyl chlorides and disulfonyl chlorides 83.1: 16.9, hydrocarbon conversion 20.7%, the yield of monosulfonchlorides on hydrocarbons 86.7%.

Example 4. Charged to the reactor 156 g of hydrocarbons with a dissolved iodine content of 0.0002% (0.0003). The process of sulfochlorination is carried out at a temperature of 18-24 ° C and at the same as in the previous examples, the supply of gases, but increase the time to 30 minutes. The sulfochloride obtained and separated from acidic impurities has the following indicators: total chlorine content is 5.45 wt.%, Hydrolyzable is 4.95 wt.%, The ratio between mono- and disulfochlorides is 71.5: 28.5. The calculated hydrocarbon conversion value is 27.4%. the yield of monosulfonyl chlorides on the reacted hydrocarbons is 75.75%.

The results for the remaining examples are given in table. 1, from the data of which it follows that the optimal concentration of iodine in the hydrocarbon feedstock is the interval of 0.0005-0.00005%. The decrease in concentration leads to a loss of selectivity, the increase is not economically justified, and

in addition, it contributes to an increase in the proportion of chlorination products formed.

A comparative analysis of the data on the composition of sulfochloride obtained without iodine and in its presence shows that

In the latter case, an increase in the selectivity of the process takes place, which is expressed at equal values of sulfochlor, the yield of alkyl monosulfonic chloride on the reacted hydrocarbon is higher by 1012 mass%, and an increase in the degree of its conversion by 1.3-1.5 times provides for obtaining alkyl sulfochloride without deteriorating it quality. In addition, from the data in the table it follows that the introduction of iodine reduces the formation of chlorination by-products, the contents of which are presented in Table. 1 in the Chlorine column in the alkyl chain.

The proposed sulfochlorination process is easy to implement under industrial conditions and does not require additional processing equipment.

In tab. Table 2 gives additional data illustrating the process productivity for the sum of mono- and disulfochlorides and for the individual monosulfochloride.

From the data table. 2 it follows that with relatively equal time of sulfochlorination (33 and 30 min) and the supply of reaction

gases in experiment 5, for example, in comparison with experiment 2, both the productivity of the process (g / h) and its selectivity increase — the yields of monoalkyl sulfonyl chloride are 78.3 and 66.4%, respectively. Similar conclusions follow from comparison of experiments 1 with experiments 3 and 8, experiment 2 with experiments 4, 5.7.

Claims (1)

The invention method of producing alkylsulfonyl chlorides by the interaction of Cs-Cia n-hydrocarbons with a gaseous mixture of chlorine and sulfurous anhydride in the presence of a initiating source of radiation, is also different in that, in order to increase the productivity of the process and improve the quality of the target products, the process is carried out in the presence of iodine introduced into the hydrocarbon feedstock in the amount of 0.0005-0.00005 wt.%. 13 21.5 13 19.5 19.5 sixteen 19.5 13.0 19.5 13 13 21.5 13 19.5 19.5 1B 19.5 13.0 19.5 13 20-23 21-24 21-24 18-22 20-25 23-25 22-25 23-24 21-24 22-26 SL with (L (Oh Yu (ABOUT 2Q 33 20 thirty thirty 25 thirty 20 thirty 20 15.2 22.2 20.75 27.4 27.7 23.2 27.45 21.3 27.1 16.3 75.1 66.4 56.4 75.7 78.3 79.0 77.2 36.7 7E, 0 / Vo from T “6 Itsa2