Technique for producing 2,5-dimethyl-2,5-hexandiol by extraction and decompression distillation method

Abstract

The invention discloses a new technology for producing 2, 5-dimethyl-2, 5-hexanediol using the method of extraction and reduced-pressure distillation. The method adopts acetylene and acetone, which are condensed with potassium hydroxide in benzene solvent and then neutralized with hydrochloric acid to get a feed solution containing hexyne-diol, oil phase and benzene. After condensation and extraction operation for twice, catalyzed hydrogenation reaction is carried out, and afterwards, the reaction product is distilled twice under reduced pressure to get the target product. The method reduces procedures such as crystallization, centrifugalization, activated carbon adsorption, etc. in prior art and develops a completely new production process, which has the advantages of high product quality, low production cost and improved working environment.

Description

technical field [0001] The invention relates to a preparation method of aliphatic alcohol, in particular to a production process of 2,5-dimethyl-2,5-hexanediol. Background technique [0002] 2,5-dimethyl-2,5-hexanediol (hereinafter referred to as hexanediol. Molecular formula C 8 h 18 o 2 "Chemical Product Handbook", Organic Chemical Raw Materials, Chemical Industry Press, 1st Edition in February 1985, Volume 1, P110-111) belongs to the category of organic chemical intermediates and fine chemical products, with strong technical specificity and high added value. inherent characteristics. The appearance is white needle-like crystals, the melting point is 87-89°C, the boiling point is 214-215°C, and the specific gravity is 0.893. It is mainly used as the basic raw material for the preparation of pyrethroid drugs, spices, artificial musk, polyethylene plastic cross-linking agent, polyester rubber and vulcanizing agent bis-2,5. It is also widely used...

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Problems solved by technology

Since the current production of hexanediol uses concentration, crystallization, centrifugation, and activated carbon adsorption to purify the product, the main problems are: long process, high labor intensity, large floor area, environmental pollution, unstable product quality, etc.

For example, the current annual production capacity of hexylene glycol in the country is about 1,600 tons, and the scale of the manufacturers is very small, with an annual production capacity of about 300-500 tons, and the product quality is unstable, and the whiteness and content of the product cannot meet the standards. The output is small and the competitiveness of the enterprise is not strong

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