A preparation process for preparing a polyoxymethylene dimethyl ether (PODE) by using methanol as a raw material, comprising using methanol and methylal as raw materials for catalytic oxidation to prepare concentrated formaldehyde having a concentration of not less than 50%; dehydrating concentrated formaldehyde to prepare a chain growth raw material; preparing a chain end-capped raw material methylal having a water content of less than 0.5% by means of reaction rectification by using chain growth raw material by-product dilute aldehydes and light-boiling circulation streams of a separation unit as raw materials; subjecting the chain growth raw material and the chain end-capped raw material to a condensation reaction, and then performing one-step multi-effect refinement to convert the formaldehyde, water, formic acid and methyl formate in the condensed product, i.e. a crude product of the polyoxymethylene dimethyl ether, into methanol by means of catalytic refinement; and separating the refined product, so as to obtain PODE3-6. The preparation process can effectively increase the utilization rate of methanol and dilute aldehydes, remove multiple azeotropic impurities, improve the quality of products, and improve the stability of a device.

» Number: WO2022033008A1 (A1)

» Publication Date: 17/02/2022

» Applicant: CHENGDU ORGANIC CHEM CO LTD CAS?[CN]; CHENGDU ZHONGKE CATALYSIS TECH CO LTD?[CN] (1)

» Inventor: LEI QIAN?[CN]; CHEN HONGLIN?[CN] (4)

» More Information

« Go to Technological Watch