Catalyst for preparing vinyl acetylene and application method thereof

Abstract

The invention discloses a catalyst for preparing vinyl acetylene and an application method thereof; the components of the catalyst include cuprous chloride, water, organic solvent, organic amine salt and organic ionic liquid. The application method includes steps that: under deoxygenation condition, the organic amine salt is dissolved in the solution of the organic solvent; and then cuprous chloride and organic ionic liquid are added to the solution; acetylene gas is introduced while the temperature is maintained constantly to produce vinyl acetylene. The invention improves the performance of an acetylene dimerization catalytic system, also increases the conversion per pass of acetylene and vinyl acetylene selectivity, produces less byproduct during reaction, greatly reduces the content of acetylene high polymer and accordingly reduces the separation difficulty and the production cost.

Description

technical field [0001] The invention relates to a catalyst for preparing vinyl acetylene and its application in the process of preparing vinyl acetylene. Background technique [0002] Chloroprene (CR) is an important variety of synthetic rubber. At present, domestic enterprises producing CR mainly use the acetylene (dimerization) method for production, that is, firstly use the acetylene dimerization method to synthesize the intermediate of chloroprene rubber—— vinyl acetylene. The catalyst used in the process of synthesizing vinyl acetylene is the famous Newland (Nieuwland) catalyst with a long history. The Nieuwland catalyst is made of cuprous chloride (Cu 2 Cl 2 ), ammonium chloride (NH 4 Cl) and hydrochloric acid (HCl) in an acidic aqueous solution. However, from the perspective of saving resources and increasing productivity, Newland catalysts still have the following deficiencies: [0003] (1) The one-way conversion rate of acetylene is low. Due to the low solubil...

AI Technical Summary

Problems solved by technology

[0003] (1) Low single-pass conversion rate of acetylene

Due to the low solubility of acetylene in the liquid-phase catalytic system, uneven gas distribution in the bubble column, low solubility of cuprous chloride and easy to be wrapped by by-product polymers, catalyst deactivation caused by acetylene entrained oxygen, etc., Therefore, the one-way conversion rate of acetylene is generally low, and the water system is generally about 11%; in the water system with special safety production measures, the one-way conversion rate of acetylene is slightly higher, but it is only about 13%.

[0004] (2) The selectivity of vinyl acetylene is not high

In the process of acetylene dimerization, due to the low catalytic selectivity of the catalyst, the content of main by-products such as acetaldehyde and divinylacetylene (DVA) in the reaction system increases

As a result, the effective conversion rate of acetylene, that is, the selectivity of vinyl acetylene decreases, which is currently only about 65%.

[0005] (3) With the occurrence of side reactions during the catalytic reaction, the production of acetylene polymers increases the production cost of the enterprise and increases the threat to the surrounding environment

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