Patent ID: 9624143
Date: 2017-04-18
CPC Classifications: C01B,C07C,C10J,Y02E,Y02P

Claim:
1. Process for preparing linear butenes from methanol, comprising: a) reacting methanol in a first reaction stage to give a first reaction mixture containing dimethyl ether, water, and optionally unreacted methanol; b) reacting dimethyl ether in a second reaction stage to give a second reaction mixture containing propene and further hydrocarbons having two, four, and five carbon atoms, where the second reaction stage is at least partly supplied with the first reaction mixture; c) working-up the second reaction mixture to give a propene-rich fraction and at least one low-propene fraction, where the low-propene fraction is at least partly recirculated to the second reaction stage; d) reacting propene in a third reaction stage to give a third reaction mixture containing ethene and linear butenes selected from the group consisting of 1-butene, cis-2-butene, trans-2-butene, where the third reaction stage is supplied at least partly with or from the propene-rich fraction; e) working-up the third reaction mixture to give a target fraction rich in linear butenes and an ethene-rich fraction, wherein the propene-rich fraction contains propane, wherein the reaction in the third reaction stage occurs in the presence of propane, and wherein a propane-rich fraction is isolated during the course of working-up the third reaction mixture.