An integrated process for production of jet-fuel range olefins from ethylene using Ni-AlSBA-15 and Amberlyst-35 catalysts

Abstract

An integrated process for the production of jet-fuel range olefins from ethylene was established by combining oligomerization of ethylene over the bifunctional Ni-AlSBA-15 catalyst with subsequent co-oligomerization of the liquid oligomer mixture over an Amberlyst-35 ion-exchange resin catalyst. The mesoporous Ni-AlSBA-15 catalyst was prepared by alumination of SBA-15 using sodium aluminate, followed by sequential ion exchange with NH4+ and Ni2+ ions. The Ni-AlSBA-15 (1.9wt% Ni and Si/Al=9) catalyst showed good catalytic activity, yielding over 99% ethylene conversion with non-Schulz-Flory type distribution of the generated hydrocarbons (C8>C6>C4>C10+) and high stability at 200°C and 10bar at a weight hourly space velocity of 0.375h−1 for 60h. Co-oligomerization of the as-synthesized liquid oligomer mixture over Amberlyst-35 ion-exchange resin under the optimized reaction conditions (5wt% catalyst loading, 100°C, 30bar N2, and 24h of reaction time) generated greater than 98% C5+ liquid product, where the C10+ olefins constituted about 42%. The catalytic activity of the Amberlyst-35 catalyst used was almost identical to that of the fresh catalyst after washing with n-heptane and drying.