Catalytic alkylation of phenol with methanol: factors influencing activities and selectivities

Activities and selectivities obtained in the catalytic alkylation of phenol with methanol, performed on four different catalysts, are compared. The tested catalysts have different but well defined acidic characteristics such as: γ-alumina containing strong Lewis acid sites, Nafion-H containing strong Brønsted acid sites, silica-alumina containing both Brønsted and Lewis sites, and Kieselguhr-supported phosphoric acid containing Brønsted acid sites of medium and weak strength. On the basis of the behaviour obtained in the cases mentioned, information about the reaction path models, mechanisms and kinetics is provided.