Improved water system nieuwland catalyst and application method thereof

Abstract

The invention relates to an improved water system nieuwland catalyst and an application method thereof. The catalyst comprises cuprous chloride, ammonium chloride and aqueous solution of hydrochloric acid in a nieuwland catalytic system, and also comprises organic amine, organic ion liquid and organic ether. In the specific preparation step, the addition sequence of the cuprous chloride, the ammonium chloride and the hydrochloric acid is adjusted, and the organic amine, the organic ion liquid and the organic ether are sequentially added into the mixture. The catalyst improves the performance of the conventional nieuwland catalyst, and can improve the conversion per pass of acetylene and the selectivity of vinyl acetylene simultaneously in a process of preparing the vinyl acetylene by applying the nieuwland catalyst; and the organic amine, the organic ion liquid and the organic ether are less in dosage and can be recycled, and thus the improved water system nieuwland catalyst has the advantages of low cost, simple method, high efficiency and the like.

Description

technical field [0001] The present invention relates to Newland catalyst and its application in the process of preparing vinyl acetylene. Background technique [0002] Newland (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. Using the acetylene dimerization method to synthesize the intermediate of neoprene - vinyl acetylene, the Newland catalyst is not only the only catalyst, but also has a long history. In the aqueous catalyst solution for synthesizing vinyl acetylene, those whose water mass accounts for less than 20% are often called non-aqueous systems, and those whose water mass accounts for more than 30% are often called aqueous systems. But, from the perspective of saving resources and increasing productivity, the Newland catalyst still has the following deficiencies: [0003] (1) The one-way conversion rate of acetylene is low. Due to the low solubility of acetyl...

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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%; although the non-aqueous system is high, it is only about 13%, and its safety is worse than that of the water system.

[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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