Degradation of n-butyl benzyl phthalate using TiO2/UV

Abstract

n-Butyl benzyl phthalate (BBP) has been classified as endocrine disrupting compound and priority pollutant. Effects of TiO2 dosage, pH, initial BBP concentration and co-existing substances on the degradation of BBP by TiO2/UV process were investigated. The optimal TiO2 dosage and pH value for the BBP degradation were 2.0 g L-1 and 7.0, respectively. The degradation rate of BBP by TiO2/UV process could be fitted pseudo-first-order kinetics. The effects of co-existing substances on the degradation rate of BBP revealed that some anions (such as BrO3 -, ClO4 - and Cr2O7 2-) could enhance BBP degradation, and other anions would restrain BBP degradation. The sequence of inhibition was PO4 3- > CO3 2- > NO3 - > SO4 2- > Cl-. The cations K+, Na+, Mg2+ and Ca2+ had the restrained effect on the BBP degradation, and the effect of Ca2+ was the strongest among four cations tested. The organic compounds acetone and methanol decreased the degradation rate of BBP. The major intermediates of BBP degradation were identified as mono-butyl phthalate, mono-benzyl phthalate and phthalic acid, and a primary degradation mechanism was proposed. © 2008 Elsevier B.V. All rights reserved.