Photodegradation of pharmaceutical drugs using Sn-modified TiO2 powders under visible ligth irradiation

Abstract

Sn-modified TiO2 powders with different amounts of tin (0, 2.4, 5.1 and 7.2 at.%) were obtained by the surfactant-assisted technique using Pluronic P123 as template. The synthesis procedure favors the formation of a mixture anatase/rutile at annealing temperatures as low as 350 C. The incorporation and further increase of the tin content promotes the transformation of anatase to rutile phase allowing to vary the anatase to rutile ratio in a controlled way, reaching the rutile phase the 96% of the mixture at a Sn content of 7.2 at.%. The synthesized materials were tested in the photocatalytic degradation of the NSAIDs, diclofenac, ibuprofen and paracetamol present in real wastewaters to evaluate their catalytic performance under visible light. The obtained results seem to indicate a certain kind of selectivity or affinity for degradation of each specific drug with a catalyst.