US Patent 9896392 Method for oligomerization of ethylene

The present invention relates to a method for oligomerization of ethylene, comprising the steps:a) feeding ethylene, solvent and a catalyst composition comprising catalyst and cocatalyst into a reactor,b) oligomerizing ethylene in the reactor,c) discharging a reactor effluent comprising linear alpha-olefins including 1-butene, solvent, unconsumed ethylene dissolved in the reactor effluent, and catalyst composition from the reactor,d) separating ethylene and 1-butene collectively from the remaining reactor effluent, ande) recycling at least a part of the ethylene and the 1-butene separated in step d) into the reactor.