Studies on the performance of annular photo reactor (APR) for pharmaceutical wastewater treatment

Heterogeneous photocatalysis in presence of nanoparticles has become a promising pathway for treatment of wastewater containing pharmaceutical components. In the present research work, degradation of aqueous solution of chlorhexidine digluconate (CHD), an antibacterial drug, has been investigated using TiO2 nanoparticles suspension in the annular photo reactor (APR) under continuous mode having the provision of catalyst recovery. During the degradation of CHD, the effects of major influencing parameters, i.e., substrate to catalyst ratio, flow rate, recycle ratio and temperature on the performance of the photo reactor and its optimization has been performed using Response Surface Methodology (RSM). Moreover, the photocatalytic efficiency of the reactor has been validated by studying the degradation of other antibiotic drugs i.e. ibuprofen (IBP), atenolol (ATL) and carbamazepine (CBZ). The continuous mode operation in photo reactor has ensured the applicability of the present system in the large volume wastewater treatment. The percentage removal of drugs using such reactor having the facility of catalyst recovery is almost same as compared to typical batch photocatalytic system. Thus, the present developed system can be utilized for the treatment of wastewater containing pharmaceutical components which are photo catalytically degradable.