Degradation of dibutyl phthalate by homogeneous photocatalysis with Fe(III) in aqueous solution

The degradation of dibutyl phthalate (DBP) photoinduced by Fe(HI) in aqueou s solution has been investigated under monochromatic irradiation and sunlig ht. Hydroxyl radicals (OH)-O-circle, responsible of the degradation, are fo rmed via an intramolecular photoredox process in excited Fe(III) aquacomple xes. The concentration in Fe(OH)(2+) in the starting Fe(III) Solution appea rs to be a controlling parameter of the degradation rate, as already stated in our previous works. The first step of the decomposition of DBP involves the hydrogen abstraction on the butyl chain mainly on the carbon in alpha -position to aromatic ring. The major primary photoproducts are hydroxy, di hydroxy and carboxylic derivatives. For prolonged irradiations, DBP and its photoproducts are completely mineralized due to the regeneration of the ab sorbing species and the continuous formation of (OH)-O-circle radicals that confers a catalytic aspect to the process. Consequently, the degradation p hotoinduced by Fe(III) could be an efficient method of DBP removal from wat er. (C) 2001 Elsevier Science B.V. All rights reserved.