Photocatalytic cleavage of C–F bond in pentafluorobenzoic acid with titanium dioxide-P25

Abstract

The photocatalytic C–F bond cleavage in pentafluorobenzoic acid (PFBA) with TiO 2-P25 using UV-C light has been investigated under different conditions. Complete cleavage of C–F is observed with TiO 2-P25 under UV-C light irradiation. Oxidants such as IO 4 −, BrO 3 −, S 2O 8 2−, H 2O 2 and ClO 3 − ions enhance the defluoridation of PFBA. The order of their activities is IO 4 − > H 2O 2 > S 2O 8 2− ≈ BrO 3 − > ClO 3 −. C–F cleavage is also influenced by the addition of inorganic anions and metal ions. The defluoridation intermediates were analyzed by GC-MS technique.