BACKGROUND Polycyclic aromatic hydrocarbons and their derivatives have harmful effects on organisms and the environment. As a typical polycyclic aromatic hydrocarbon, 2-naphthol is a persistent, highly toxic organic pollutant that biodegrades very slowly and thus its elimination is of high priority. RESULTS Ag-deposited TiO2/cordierite honeycomb monoliths (CHMs) have been successfully applied to the photocatalytic degradation of 2-naphthol. The physical properties of the catalyst were characterized using various techniques. Deposition of metallic silver on a thin layer of TiO(2)adhering to the inner walls of the CHM reduces the bandgap energy and lowers the recombination rate of photogenerated electrons and holes. The optimal photocatalyst (0.4Ag-deposited S700-ST) exhibits a first-order degradation rate ofk= 0.048 min(-1)with 91.0% decomposition of 2-naphthol after 240 min of irradiation with 12 W, 395 nm LED light. The 0.4Ag-deposited S700-ST material is stable throughout four photocatalytic reaction cycles. CONCLUSIONS The work presented describes the development of a robust, stable TiO2-coated CHM that overcomes the recovery drawbacks of nano-TiO2-based slurries in photocatalytic wastewater treatment. (c) 2020 Society of Chemical Industry