Electrosynthesis of benzoquinone from phenol was investigated in acetonitrile-water mixtures on alpha-PbO2 and beta-PbO2 electrodes. The influence of water concentration, electrolysis potential, initial phenol concentration and temperature on benzoquinone production was also studied. Different electrocatalytic activities of alpha and beta structures of PbO2 were determined. (c) 2005 Elsevier Ltd. All rights reserved.