Method for manufacturing dimethyl ether with solid acid catalysis methanol dehydration reaction

Abstract

A method that the solid acid catalyzes the methanol to dehydrate and react to produce the dimethyl ether is provided. Under the condition that the solid acid catalyst exists, the liquid state materials are adopted as the chill materials to control the catalyst bed temperature distribution. The reaction conditions are that the reaction pressure is 0.2MPa to 4.0 MPa, the reaction temperature is 120 DEG C. to 400 DEG C. and the feeding air speed is 0.5 to 20.0. The solid acid catalysts are the cation exchange resin, the ZSM-5 molecular sieve, the ZSM-35 molecular sieve, the MCM-22 molecular sieve, Gamma-alumina or the mixture of the above. The invention can make the bed temperature rapidly lower in the range set by the process via filling the cold-shocking materials. Because the catalyst bed temperature is distributed evenly, the invention greatly reduces the occurrence of the side-effects and the carbon deposit on the catalysts and prolongs the service life of the catalysts.

Description

technical field [0001] The invention relates to a method for producing dimethyl ether from methanol, in particular to a method for continuously producing dimethyl ether by using a solid acid catalyst and dehydrating methanol in gas phase. Background technique [0002] Dimethyl ether is a widely used chemical product and fuel substitute. Dimethyl ether was first produced by methanol dehydration, and the reaction was carried out in the liquid phase. The main disadvantages were severe equipment corrosion, harsh operating conditions, and serious environmental pollution. At present, the production of dimethyl ether by dehydration of methanol with solid acid catalyst is the main method and future development trend in industry. [0003] USP6740783 discloses a molecular sieve catalyst for the production of dimethyl ether from methanol. The protons on the molecular sieve catalyst are replaced by metals or amines, and methanol vapor is dehydrated on the molecular sieve catalyst. [...

AI Technical Summary

Problems solved by technology

Dimethyl ether was first produced by methanol dehydration, and the reaction was carried out in the liquid phase. The main disadvantages are severe equipment corrosion, harsh operating conditions, and serious environmental pollution.

In industrial production, there are problems such as difficult control of catalyst bed temperature or uneven temperature distribution, so it is difficult for large-scale chemical industrial production