A novel double-cylindrical-shell photoreactor immobilized with monolayer TiO2-coated silica gel beads for photocatalytic degradation of Rhodamine B and Methyl Orange in aqueous solution

A novel double-cylindrical-shell (DCS) photoreactor immobilized with monolayer TiO2-coated silica gel beads was developed and successfully applied for the degradation of Rhodamine B (RhB) and Methyl Orange (MO). Photocatalytic degradation of RhB using the developed photocatalytic reactor was confirmed by UV-VIS-NIR spectroscopy analysis and kinetic studies. The operational parameters including flow rate, initial concentration and repetitive operation for the degradation of RhB was investigated to optimize the developed photocatalytic reactor. Electrical energy per order (Ea)) was used to calculate the electrical energy consumption for the degradation of RhB and MO using the developed photocatalytic reactor. The developed photocatalytic reactor, in comparison with reported slurry-suspension and thin-film photoreactors, showed higher efficiency, lower energy consumption and better repetitive operation performance for the degradation of RhB and MO. The TiO2-coated silica gel beads immobilized DCS photoreactor is a promising alternative for the decomposition of recalcitrant organic pollutants in wastewater. (C) 2014 Elsevier B.V. All rights reserved.