ZEOLITE-BETA AS A CATALYST FOR ALKYLATION OF ISOBUTANE WITH 2-BUTENE - INFLUENCE OF SYNTHESIS CONDITIONS AND PROCESS VARIABLES

The continuous alkylation of isobutane with 2-butene was carried out on a series of beta catalysts prepared by two different synthesis procedures, involving the use of amorphous silica (Aerosil) and TEOS as silica source. The stability of the zeolite towards dealumination during the activation steps was seen to increase with Si/Al ratio and crystal size of the beta catalyst. The most stable catalysts were also the most active and selective for alkylation, giving a higher TMP/DMH ratio during the initial reaction stages. These samples also deactivate at a lower rate with TOS. The observed differences in catalytic activity and selectivity were attributed to differences in both total acidity and acid strength distribution. Finally, the influence of reaction temperature and isobutane/2-butene ratio on the catalytic behavior were also investigated.