SU914545A1 - Process for producing vinyl chloride - Google Patents

Description

The invention relates to the synthesis of vinyl chloride, which is used in the manufacture of polymeric materials.

A known industrial method of producing vinyl chloride by thermal dehydrochlorination of 1, 2-dichloroethane at 550 ° C [13.

The disadvantages of the method are the complexity of the hardware, due to the use of high temperatures, and the insufficiently high productivity of the process.

Closest to the proposed technical essence and the achieved result is a method for producing vinyl chloride by dehydrochlorination of 1,2-dichloroethane at 400-450 ° C, in the presence of a nickel on alumina catalyst. Dichloroethane conversion 94-97%, vinyl chloride selectivity 9θ% лорида 23.

The disadvantages of the known method are the use of sufficiently high temperatures, as well as the necessity of the stage of processing the used catalyst with hydrogen to convert it to the active form. All this in general complicates the process technology.

The goal is to simplify process technology.

The goal is achieved by the method of producing vinyl chloride, which consists in the fact that 1,2-dichloroethane is subjected to dehydrochlorination at 300-400 ° C in the presence of magnesium chloride catalysts on aluminum oxide, with an atomic ratio of magnesium and aluminum in the used catalyst (0.2-0, 5): 1.

For the preparation of the catalyst can be used <G - and C, modifications A 1 ^ 3. The catalyst is prepared by impregnating the alumina granules with an aqueous solution of magnesium chloride, followed by evaporation of the solution, drying and calcining con-4 3 914545 4;

. t'aktnoy mass in air at 500 ^e C for 4 hours the catalyst composition may vary within a Mg: A1 (0.2-0.5): 1 *, g-at. Catalyst catalyst regeneration is carried out by burning coke with atmospheric oxygen at 35 ° C.

The proposed method for producing vinyl chloride is tested in laboratory conditions.

Example 1. The catalyst MDC1 ₂ / A1 ₂ 0 ₃ , MD: A1 0.2: 1. The experiment is carried out on a flow-through installation with a stationary catalyst bed. 8, a pyrex reactor equipped with a thermocouple pocket was placed with 9 ml of catalyst (grain size 0.8-1.5 mm), the plant was purged with nitrogen, and a temperature of 400 ° C was set in the catalyst zone. The supply of 1,2-dichloroethane is carried out by a syringe with a space velocity of 1, '13 4 ~ ί. The reaction is carried out for two hours.

The reaction products are analyzed by gas-liquid and gas absorption chromatography.

PRI me R 2. Catalyst MDC1 ₂ / D1 _a 0 ₃ , Md: A1 0.5: 1.

The conditions of the experiment are similar to example 1, except for the reaction temperature, which is 35 ° C.

Example Z. Catalyst, MdC1 _g / A1 _g 0 ₃ , Md: A1 0.5: 1.

Conditions of the experiment analogous to Example 1 except for the reaction temperature which is ³⁰⁰ C.

Table 1 shows the results

tests. T% b l c a 1 - At- measures Chloroethane Conversion, 1,2-dimole. % Content vinyl chloride in contact gas, mol.% 1 100 88 2 91 97 3 54 95

Table 2 shows the material balance data by examples.

table 2

Example I ® Submitted 1,2-dichloroethane, g Received * 1 25,4 Vinyl chloride, g 14.3 Other, l 0.7 2 25,4 1,2-Dichloroethane, g 2,3 • Vinyl chloride, g 14.1 Other, l 0.16 3 25,4 1,2-Dichloroethane, g 11.7 Vinyl chloride, g 8.2 Other, l 0.16

* Excluding hydrogen chloride,

The sum of methane, propylene, CO, CO ^, acetylene and ethylene.

Others - a light fraction with a boiling point above the boiling point of vinyl chloride.

Claims (1)

Claim A method of producing vinyl chloride by dehydrochlorination of 1,2-dichloroethane at elevated temperature in the presence of a catalyst containing a modifier on alumina, characterized in that, in order to simplify the process technology, magnesium chloride is used as a modifier at an atomic ratio of magnesium to aluminum in the used catalyst equal to 0.2-0.5; 1 and the process is carried out at 300-400 ° C.