Olefin separation process

摘要

An improved process for the separation of olefins from a hydrocarbon feed mixture comprising olefins and saturates which process uses an adsorbent comprising sodium type X or sodium type Y zeolite to selectively adsorb the olefins. The improvement comprises employing an adsorbent produced by the steps of: contacting a precursor mass comprising type X or type Y zeolite having a Na2O/Al2O3 ratio less than about 0.7 with an aqueous sodium hydroxide solution at ion exchange conditions to effect the addition of sodium cations to the mass and the removal of a small amount of silica and alumina, washing the mass with water to remove excess sodium hydroxide solution; and, at least partially dehydrating the mass at dehydrating conditions thereby producing an adsorbent which has both increased capacity for olefins and decreased catalytic activity.