A green hydrolysis process for preparing benzyl alcohol with high selectivity

Abstract

The invention discloses a high-selectivity green hydrolysis technology for preparing benzyl alcohol. The high-selectivity green hydrolysis technology includes the steps that sodium formate, benzyl chloride, water and organic tertiary amine catalysts are put into a reactor in the molar ratio of (1.05-1.1):1:7.0:0.02, sufficiently mixed and stirred, and subjected to normal-pressure reacting for 8 h to 9 h at the temperature of 100 DEG C to 115 DEG C, heating is stopped, the temperature is reduced to be 95 DEG C to 105 DEG C, caustic soda with the molar weight equal to the molar weight of the benzyl chloride is put, and the mixture continues to be reacted for 2 h to 3 h; the reacted mixture is filtered, solid sodium chloride is removed, the liquid-phase product is cooled, and the organic-phase product is separated; the organic-phase product is subjected to rectification separation, and the high-purity benzyl chloride is obtained; the water-phase product is returned to the reactor again, and repeated hydrolysis reacting is carried out after the raw materials are supplemented; According to the high-selectivity green hydrolysis technology, the benzyl chloride is subjected to hydrolysis with the sodium formate as an assistant and the organic tertiary amine as a catalyst to prepare benzyl alcohol, and the adopted organic organic tertiary amine catalysts are low in price and high in catalysis efficiency; the water-phase product obtained through the reaction can be recycled, high-salt wastewater in the production process of the benzyl alcohol is solved, and meanwhile the content of the dibenzyl ether is greatly reduced, wherein the content of the dibenzyl ether is lower than 3.5%.

Description

technical field [0001] The invention relates to the field of organic chemical synthesis, in particular to a green hydrolysis process for preparing benzyl alcohol with high selectivity. Background technique [0002] At present, the production method of benzyl alcohol mainly adopts benzyl chloride primary atmospheric pressure alkaline hydrolysis and high-pressure secondary hydrolysis, and high-pressure secondary hydrolysis is divided into alkaline hydrolysis and non-alkali hydrolysis. The main problem faced by the existing atmospheric pressure hydrolysis is that the process produces a large amount of high-salt wastewater and by-product dibenzyl ether, and the treatment cost is relatively high; Hydrochloric acid needs to be treated; at the same time, high-pressure hydrolysis requires high equipment usage. In addition, the utilization rate of existing process equipment is low, and the concentration of lye is low, about 8-13%, while the amount of water used in the non-alkali hyd...

AI Technical Summary

Problems solved by technology

The main problem faced by the existing atmospheric pressure hydrolysis is that the process produces a large amount of high-salt wastewater and by-product dibenzyl ether, and the treatment cost is relatively high; Hydrochloric acid needs to be treated; at the same time, high-pressure hydrolysis requires high equipment usage

In addition, the utilization rate of existing process equipment is low, the concentration of lye is low, about 8-13%, and the amount of water used in the non-alkali hydrolysis process is relatively large, up to 5 times the mass of benzyl chloride

[0003] Wastewater treatment is one of the biggest environmental problems today. The treatment of high-salt wastewater and waste acid has brought huge cost pressure and environmental protection pressure to enterprises, and its related treatment technology has also become a problem that plagues the development of enterprises.