Pharmaceutical wastewater treatment by Titanium dioxide photocatalysis : case of Escitalopram oxalate

Abstract

Nowadays, research has been conducted on the environmental concern that face the improper discarding of the water influents from the conventional wastewater treatment plants. They were not able to remove pharmaceutical traces that come from hospitals, which can have negative impacts on the marine organisms. Escitalopram oxalate (ESC) is one of the micropollutants that cannot be removed by the conventional wastewater treatment processes. Photocatalysis is an innovative AOP method to degrade such drugs. First, adsorption on the photocatalyst (TiO2) surface has been conducted by mixing four different concentrations of ESC (0.02, 0.03, 0.05, 0.07 g/L) with four masses of TiO2 (0.3, 0.5, 0.7, 1g). After 24 hours, a UV lamp was inserted inside the photocatalytic reactor and ESC photodegradation takes place for each experiment for 3 hours of UV exposure. After studying the appropriate kinetics, the optimum TiO2 mass was found to be 0.7g. The adsorption kinetic follows Langmuir isotherm model and the photocatalytic process follows Langmuir-Hinshelwood model.