Decomposition of several environmental pollutants in water using perylene adsorbed on silica gel (Pe/SiO2 powder) as a photocatalyst under the visible-light irradiation have been studied. The Pe/SiO2 powder was prepared by mixing a toluene solution of the perylene with silica gel followed by evaporating the toluene. Irradiation by visible light (>420nm) of the methyl orange aqueous solution with the Pe/SiO2 powder in the presence of ascorbic acid resulted in the decomposition of the methyl orange. The rate of decrease of the methyl orange reached 99% by visible light irradiation for 20 min. The reaction also occurred by the irradiation of sunlight. In addition, the irradiation of visible light also led to the decomposition of imidacloprid using Pe/SiO2 in the presence of ascorbic acid. Furthermore, irradiation by visible light (>420 nm) of a pentachlorophenol aqueous solution with the Pe/SiO2 powder resulted in the decomposition of the pentachlorophenol. The possible mechanisms of these reactions are discussed. (C) 2016 Elsevier B.V. All rights reserved.