Formation of Trimethylpentanes from Isobutane and 1-Butene Catalyzed by Sulfated Metal Oxides

The gas-phase alkylation of 1-butene with isobutane was carried out over superacids of sulfated metal oxides, SO4/Fe2O3, SO4/Al2O3, SO4/TiO2, SO4/SnO2, and SO4/ZrO2, at 0°C; SO4/SnO2 gave the highest yield of trimethylpentane (TMP). It was proved from relationship between the catalyst acidities and the yields of C8 paraffins that the first intermediate species was a tbutyl cation formed on the superacidic Lewis site by abstraction of H? followed by the alkylation with butenes to form TMP.