Method for synthesizing PODE (polyformaldehyde dimethyl ether)

Abstract

The invention relates to a method for synthesizing PODE (polyformaldehyde dimethyl ether), which mainly solves the problems of high content of methylal and low yield coefficient of poly products in the traditional process of synthesizing the PODE with carbinol and trioxymethylene as raw materials. The method adopts the carbinol, the methylal and the trioxymethylene as the raw materials, and the raw materials contact a catalyst under conditions that reaction temperature is 50-200 DEG and reaction pressure is 0.1-10 MPa so as to react to generate the PODE, wherein the catalyst is at least one of Beta zeolum, ZSM-5 molecular sieve and MCM-22 or MCM-56 zeolum molecular sieve. The method preferably solves the problems and can be used for the industrial production of the PODE.

Description

technical field

[0001] The invention relates to a method for synthesizing polyoxymethylene dimethyl ether. Background technique

[0002] Polyoxymethylene dimethyl ether, polyoxymethylene dimethyl ethers (PODE), is a general term for a class of substances, and its simplified formula can be expressed as CH 3 O(CH 2 O) n CH 3 , when the value of n is 2-10, it can be used as a diesel additive, and the addition amount in diesel can reach 30% (v / v). PODE has higher oxygen content (ranging from 42 to 51%) and cetane number (above 30), which can improve the combustion status of diesel in the engine, increase thermal efficiency, and reduce solid pollutants, COx and NOx emissions. It is reported that adding 5-30% CH 3 OCH 2 OCH 3 It can reduce NOx emission by 7-10%, and reduce PM by 5-35%. Adding PODE can not only replace part of diesel, but also improve the combustion efficiency of diesel. Therefore, it is considered to be a diesel additive with great application prospects. ...