Synthetic method of polyoxymethylene dimethyl ether

Abstract

The invention relates to a polyformaldehyde dimethyl ether synthesis method which mainly solves the problems of difficult catalyst separation, low raw material conversion rate and poor product selectivity in the prior art. The technical scheme of the polyformaldehyde dimethyl ether synthesis method comprises the following steps: by taking methanol, methylal and polyformaldehyde as raw materials, under the conditions that the reaction temperature is 70-200 DEG C and the reaction pressure is 0.2-6 MPa, enabling the raw materials to be in contact with a catalyst, and reacting to generate polyformaldehyde dimethyl ether, wherein the weight ratio of the methanol, the methylal and the polyformaldehyde is (0-10):(0-10):1, and the amounts of the methanol and the methylal can not be 0 at the same time; the amount of the catalyst accounts for 0.1-5.0% of the weight of the raw materials; and the used catalyst comprises the following components in parts by weight: a) 30-80 parts of carrier, which is at least one selected from SBA-15, MCM-41 or MCM-22 molecular sieve, and b) 20-70 parts of solid super-strong acid carried thereon, which is at least one selected from SO4<2-> / ZrO2, SO4<2-> / Fe2O3, Cl<-> / TiO2 or Cl<-> / Fe2O3. Thus, the problems are well solved; and the polyformaldehyde dimethyl ether synthesis method can be used for industrial production of polyformaldehyde dimethyl ether.

Description

technical field [0001] The invention relates to a method for synthesizing polyoxymethylene dimethyl ether, in particular to a method for synthesizing polyoxymethylene dimethyl ether with paraformaldehyde as a raw material. Background technique [0002] In recent years, with the deepening influence of the industrial revolution and my country's unique resource pattern of "more coal, less oil, and gas", my country's oil resources have become increasingly tense, and the pressure on oil supply has increased unprecedentedly. It is estimated that in the next 10-20 years, my country's oil supply rate will only be ~50%. How to use our country's rich coal resources to solve our country's energy crisis has become an urgent problem for scientific researchers. Therefore, the development of new oil substitutes from coal-based methanol has attracted increasing attention. [0003] DME was first proposed as a diesel additive. However, due to its poor cold start performance, high vapor pres...

AI Technical Summary

Problems solved by technology

[0007] The technical problem to be solved by the present invention is that there are problems in the synthesis of polyoxymethylene dimethyl ether with methanol, methylal and paraformaldehyde as reaction raw materials in the prior art, such as difficult catalyst separation, low conversion rate of raw materials, and poor product selectivity. A new synthetic method of polyoxymethylene dimethyl ether