Phenol/acetone cogeneration via cumene hydroperoxide (CHP) cleavage has been demonstrated using various classes of novel solid acid catalysts. Mineral acid-treated montmorillonite silica-alumina clays, heteropoly acids impregnated into Group TV oxide supports, fluorophosphoric acid and HF-treated oxides, as well as montmorillonite clays modified with heteropoly acids or certain Lewis acids, are each effective. The influence of solid acid structure upon phenol yields has been examined while minimizing by-product acetophenone, 2-methylstyrene, 2-phenyl-2-propanol, mesityl oxide formation, etc. For the more promising candidates, decomposition of 80% CHP solutions in continuous, plug-flow reactor systems, under mild conditions (ca. 60 degrees C at LHSVs approximate to 10) has been realized.