Preparation method and device for p-cresol

Abstract

The invention provides preparation method and device for p-cresol. The method includes: performing a reaction to toluene and sulfuric acid to prepare sulfonic acid; performing a reaction on the sulfonic acid with slurry to prepare sodium sulfonate, the slurry being prepared from solid sodium sulfite, in an alkali fusion section, with dry condensed water; treating the sodium sulfonate under alkaline conditions to generate sodium phenolate; treating the sodium phenolate under acidic conditions to generate the p-cresol. The method shortens process of the p-cresol and reduces equipment investment,greatly reduces the unit consumption of raw materials, energy and water, can completely solve the problems of high treatment difficulty and cost on waste water and waste gas in a p-cresol productionprocess in the prior art, can improve automation level of equipment by changing most of batch production into continuous production, and improves work environment.

Description

technical field [0001] The invention relates to the field of chemical industry, in particular to a preparation method and equipment of p-cresol. Background technique [0002] p-cresol is an important fine chemical intermediate, mainly used in the synthesis of medicines, pesticides, spices, dyes, antioxidants, polymerization inhibitors, ultraviolet absorbers, fuel additives, rubber additives, etc., and is an important raw material for fine chemicals. The main synthesis methods of p-cresol include toluene sulfonation alkali fusion method, phenol methylation method, isopropyl toluene method, p-toluidine method, etc. p-cresol, o-cresol, m-cresol, etc. are produced simultaneously in p-cresol industrial production. Cresol 3 isomers. The domestic industrial production of p-cresol generally adopts the toluene sulfonation alkali fusion method, and most of the production process adopts batch production, and the neutralization is carried out by the sodium sulfite solution produced in ...

AI Technical Summary

Problems solved by technology

[0011] Based on the problems existing in the prior art, the purpose of the present invention is to provide a preparation method of p-cresol; the method shortens the existing p-cresol process flow, reduces equipment investment, and greatly reduces the unit consumption of p-cresol raw materials, energy Unit consumption, water consumption, and can completely solve the problem of difficulty and high cost of wastewater and waste gas treatment in the current p-cresol production process, improve the automation level of equipment, change most of the intermittent production into continuous production, and improve the working environment

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