| abstract |
The present invention discloses a method, system and reaction system for the oligomerization of ethylene to form an oligomer product in a reaction zone using a catalyst system having i) an N2 -phosphinyl amidine chromium compound complex comprising, The chromium component of an N2 -phosphinylformamidine chromium compound complex, an N2 -phosphinylguanidine chromium compound complex, or any combination thereof, and ii) an alumoxane. Prior to contacting with the catalyst system, ethylene can be contacted with an organic reaction medium to form an ethylene feed mixture. The ethylene feed mixture can be contacted with the catalyst system either inside or outside the reaction zone. |