Assessment and influence of operational parameters on the TiO2 photocatalytic degradation of sodium benzene sulfonate under highly concentrated solarlight illumination

Sodium benzene sulfonate (BS) was decomposed in aqueous TiO2 dispersions un der highly concentrated solar light illumination to examine the photocataly tic characteristics of a parabolic round concentrator (PRC) reactor to degr ade the pollutant without visible light absorption. The effects of such ope rational parameters as initial concentration, volume of the aqueous BS solu tion, oxygen purging, and TiO2 loading on the kinetics of decomposition of BS were investigated. An effective photodegradation necessitates a suitable combination of initial volume and concentration of BS solution. Relative t o atmospheric air, oxygen purging significantly accelerates the degradation process at high initial concentrations of BS (0.40 mM or 1.0 mM). Optimal TiO2 loading was 9 g l(-1), greater than previously reported. Elimination o f TOC (total organic carbon) followed pseudo first-order kinetics in the in itial stages of the photodegradation process. The relative photonic efficie ncy for the photodegradation of BS is zeta (rel) = 1.0. (C) 2001 Elsevier S cience Ltd. All rights reserved.