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

The photocatalytic C–F bond cleavage in pentafluorobenzoic acid (PFBA) with TiO2-P25 using UV-C light has been investigated under different conditions. Complete cleavage of C–F is observed with TiO2-P25 under UV-C light irradiation. Oxidants such as IO4−, BrO3−, S2O82−, H2O2 and ClO3− ions enhance the defluoridation of PFBA. The order of their activities is IO4− > H2O2 > S2O82− ≈ BrO3− > ClO3−. C–F cleavage is also influenced by the addition of inorganic anions and metal ions. The defluoridation intermediates were analyzed by GC-MS technique.

UV-C light is found to be more efficient than UV-A light in the photocatalytic cleavage of C–F bond in pentafluorobenzoic acid using TiO2-P25. Oxidants, inorganic anions and metal cations have strong influence on the defluoridation rate. Figure optionsDownload as PowerPoint slide