Removal of non-steroidal anti-inflammatory drugs from primary and secondary effluents in a photocatalytic membrane reactor

BACKGROUND: The pollution of the aquatic environment by pharmaceuticals has become a serious problem. Conventional technologies applied in water or sewage treatment plants are not effective in drugs removal, therefore there is an urgent need to develop new methods. RESULTS: The removal of diclofenac (DCF), ibuprofen (IBU) and naproxen (NAP) sodium salts in a photocatalytic membrane reactor (PMR) utilizing direct contact membrane distillation and UV-C radiation from ultrapure water, tap water, primary effluents (PE) and secondary effluents (SE) of municipal wastewater treatment plant is presented. When PE were used as feed and TiO2 loading of 0.5 g dm(-3) was applied, DCF was removed completely, IBU amount decreased for 73% and NAP for 90%. In the case of SE, DCF, IBU and NAP concentrations decreased by 100%, 93% and 94%, respectively (1.5 gTiO(2) dm(-3)). Mineralization was low and did not exceed 14% for PE and 23% for SE. No drugs were found in the distillate, however, it contained high level of N-NH4+, especially in PE. CONCLUSION: The hybrid system can be an effective technology for the removal of pharmaceuticals from SE and PE, however, owing to membrane fouling the latter should be pretreated before application in the PMR. (C) 2014 Society of Chemical Industry