Enhanced photocatalytic degradation of ibuprofen in aqueous solution under visible-light irradiation: Effects of LaFeO3 and Cu/LaFeO3

Abstract

The efficiency of LaFeO3 and Cu-doped LaFeO3 nanopowders in the photocatalytic degradation of ibuprofen (IBP) has been investigated. Aqueous solutions of IBP in the presence of photocatalyst, of H2O2, and both photocatalyst and H2O2, were irradiated under visible-light. The experiments were carried out on aqueous suspensions containing 5.0 x10-5 M of IBP, 0.003 M of H2O2, 0.130 g L-1 of catalyst. The concentration of H2O2 corresponded to a mole amount that largely exceeded the amount for the complete oxidation of IBP. Moreover, concentration of H2O2 was about 1/30 than that used in typical studies on the heterogeneous Fenton-like process. The composition of the reaction solution during photocatalytic experiment was followed by UV-Vis spectroscopy and HPLC. The results showed the higher photocatalytic activity of Cu-doped LaFeO3 (5 and 10 mol%) compared to pure LaFeO3 [1]. With both photocatalysts the main degradation product of IBP was 4-isobutylacetophenone (4-IBAP), which showed a slower photocatalytic degradation than the parent compound.