Friedel-Crafts alkylations of aromatic hydrocarbons have been carried out in the presence of a series of clay catalysts originating from K10 montmorillonite and Kunipia. It was found that the iron pillared clays (FePILCs) were the most efficient catalysts producing quantitative conversions with greatly reduced amounts of catalysts in lesser reaction times. Their efficiency is attributed to the higher Fe3+ contents in the catalysts and the pillaring effect.