Preparation of Al–Cu pillared clay catalysts for the catalytic wet oxidation of reactive dyes

Al–Cu pillared clays were prepared by direct introduction of Al–Cu pillaring solution into the dilute bentonite suspension. Al–Cu pillared clays had d0 0 1 spacing of about 18 Å and had surface area of about 140 m2/g or higher. Al–Cu pillared clays showed excellent activity toward the catalytic wet peroxide oxidation (CWPO) of reactive dyes. Complete removal of reactive dyes could be achieved within 20 min at atmospheric pressure and 80 °C which are extremely milder operation condition when compared with the conventional catalytic wet oxidation process. The pillared clays were also stable against the leaching out of Cu.