Photocatalytic Removal of Pharmaceuticals by Immobilization of TiO2 on Activated Carbon by LC-MS/MS Monitoring

Abstract

Pharmaceutically active compounds (PhACs), Diclofenac (DFC), Ibuprofen (IBU), and Paracetamol (PRC) are anti-inflammatory drugs commonly detected in wastewater. These micropollutants (pharmaceuticals) are not completely removed in conventional wastewater treatment plants. Therefore, alternative treatment methods are needed. In this context, the removal of three pharmaceuticals was investigated by the immobilized TiO2 method on activated carbon. Emphasis was given on the effect of pH (3-5-7 and 9) and catalyst loading (0.025-0.05-0.075-0.1 and 0.125 g/L). Tube reactor with UV lamp (254 nm) system was used in the study. Concentration of PhACs was analyzed by LCMS/MS. Characterization of AC/TiO2 composite was analyzed by XRD, Raman, and SEM. At the end of the study, the highest removal efficiencies were obtained for IBU and PRC at acidic pH while for DFC at neutral pH. It was determined that the removal efficiency increased as the dose of the catalyst increased for all three pharmaceuticals. The kinetic studies were fitted using the first order Langmuir-Hinshelwood model, obtaining a high accuracy based on R-2 value.