PROCESS TO MAKE PROPYLENE FROM ETHYLENE AND EITHER DIMETHYL ETHER, OR METHANOL AND DIMETHYL ETHER

摘要

The present invention is a process to make propylene comprising:;a) providing a reaction zone containing a catalyst;b) introducing a feedstock comprising ethylene, dimethyl ether or methanol and dimethyl ether comprising at least 1000 wppm of dimethyl ether, optionally steam into said reaction zone and into contact with said catalyst;c) operating said reaction zone at temperature and pressure conditions to produce an effluent comprising propylene, hydrocarbons, steam, optionally unconverted methanol and/or unconverted dimethyl ether and optionally unconverted ethylene;d) sending the effluent of step c) to a fractionation zone to recover propylene optionally methanol and for dimethyl ether and optionally ethylene;e) optionally recycling at least a part of methanol and for dimethyl ether and optionally recycling at least a part of ethylene to the reaction zone at step b);wherein the catalyst is an acid and the temperature at the inlet of the reaction zone is under 280° C. and advantageously from 50 to 280° C.