Process for refining anisole

Abstract

The invention discloses a process for refining anisole. According to the process, mixed liquid of any one of 1,4-butanediol, 1,3-butanediol, 2,3-butanediol and 1,2-butanediol and sulfolane with the mass ratio being (1 to 10):1 is adopted as an extracting agent, azeotrope of the anisole and water is extracted in an extracting tower through the extracting agent, water is extracted from the tower topof the extracting tower, a tower substrate enters a rectifying tower, and after rectifying, the anisole is extracted from the tower top of the rectifying tower. According to the method, the anisole and the water are separated, the tower height and the reflux ratio are decreased after the extracting agent is used, the separating efficiency is improved, energy consumption is greatly lowered, and the separating cost is lowered. The process has the advantages that the separating efficiency is high, the purity of the anisole is high, and the extracting agent can be recycled.

Description

technical field [0001] The invention belongs to the technical field of separation of anisole, and in particular relates to a method for separating anisole and water. Background technique [0002] Anisole, also known as anisole, anisole, and methoxybenzene, is an important chemical raw material. Because of its special fragrance, it can be used as an additive to soaps and detergents; Used as an intermediate in insecticides; due to its large dielectric constant and high boiling point, it can be used as an excellent general reagent, initiator, solvent, thermostat filler, etc., and it can also be used as a substitute for gasoline additives because it can increase the octane number of gasoline MTBE can also be used as solvent, synthetic resin and fuel additive in printing industry and paint industry. In recent years, the market demand for anisole has increased dramatically. [0003] The synthetic method of anisole mainly contains dimethyl sulfate method, dimethyl carbonate metho...

AI Technical Summary

Problems solved by technology

The dimethyl sulfate method has the advantages of low reaction temperature, good selectivity of the target product, and low cost, but the dimethyl sulfate used is highly toxic, and phenol needs to be converted into sodium phenate during the production process, requiring the use of a large amount of A large amount of sodium hydroxide will produce a large amount of saline waste water, and the post-treatment is difficult, resulting in serious environmental pollution of this method, and this process has been eliminated; while the dimethyl carbonate method and the methanol method use green methylation reagents dimethyl carbonate and methanol, No solid waste is generated during the production process, and they are two green synthetic routes with great industrial application prospects

[0004] Both the dimethyl carbonate method and the methanol method produce water in the products, and water and the target product anisole can form an azeotrope, which makes the separation and purification of anisole difficult and becomes a shortcoming that limits its industrial application

Although the difference in polarity between anisole and water can be achieved by phase separation, the phase separation takes a long time and requires the addition of a large amount of demulsifier. What is obtained is only crude anisole with less water content, and a large amount of demulsifier is required. The dehydrating agent magnesium sulfate, calcium chloride, etc. continue to dry and dehydrate and filter to meet the requirements of commercially available anisole. The separation is time-consuming and laborious, and more solid waste is generated. At the same time, the water phase is difficult to handle because it contains anisole. Therefore, it is imperative to develop a separation process with high separation efficiency, no pollution, and low energy consumption.

Images