Patent ID: 7923591

Claim:
A method for manufacturing at least one lower olefin from an oxygenate-containing first reaction mixture ( 11 ) through conversion at a catalyst ( 20 ) to an olefin and paraffin-containing second reaction mixture ( 21 ), which is fed to a first separation stage ( 30 ), in which at least one lower olefin-containing first product stream ( 31 ) and one higher olefin and paraffin-containing second product stream ( 32 ) are separated, wherein the second product stream ( 32 ) is further separated into a higher boiling hydrocarbons stream ( 42 ) and a third product stream ( 41 ) in a second separation stage ( 40 ), the third product stream ( 41 ) is fed to an extractive distillation unit ( 50 ) wherein a paraffin-enriched fraction ( 51 ) is extracted by means of a selective polar solvent to leave a fourth product stream ( 52 ), which is fed to a solvent stripper ( 80 ) where solvent is removed from said fourth product stream ( 52 ) and recycled to the extractive distillation ( 50 ), leaving a rafinate ( 81 ) which is at least partially recirculated to the catalyst ( 20 ).