Isobutane/2-butene alkylation catalyzed by chloroaluminate ionic liquids in the presence of aromatic additives

The effect of adding aromatic compounds and varying the AlCl3 molar fraction on the catalytic performance of chloroaluminate ionic liquids in isobutane/2-butene alkylation was investigated. 27Al NMR results and comparison with alkylation catalyzed by solid AlCl3 reveal that the activity of the ionic liquids presumably comes from traces of AlCl3 or Al2Cl6. The addition of benzene increases the selectivity of C8 as well as the TMP:DMH ratio in the alkylate. The performance of the modified catalyst is optimized at high isobutane to 2-butene ratios and low temperatures. The used catalyst can be regenerated by replenishment of the aromatic additives.