A new hetero-junction p-CuO/n-ZnO for the removal of amoxicillin by photocatalysis under solar irradiation
Résumé
The main objective of this study was to evaluate the efficiency of a new hetero-junction p-CuO/n-ZnO assisted photo-catalytic process for the degradation of amoxicillin (AMX). The catalysts is synthesized by chemical route and characterized by X-ray diffraction, scanning electron microscopy (SEM), thermal analysis, BET specific surface area and photo-electrochemistry. The initial AMX concentration, photo-catalyst nature, catalyst dose and initial pH of the solution were optimized in order to evaluate the mineralization extent. AMX (50 mg/l) was almost entirely removed after 4 h of exposure to solar irradiation at pH similar to 11, by using the hetero-junction ZnO/CuO (50:50 wt%). The final AMX concentration was determined by high performance liquid chromatography (HPLC) equipped with a photodiode array detector. The analysis of NO(3)(-)and SO42- released by the degradation reaction were quantified by ionic chromatography and the total organic carbon (TOC) indicated a high mineralization degree of AMX. Kinetic analysis suggested that the AMX degradation obeys to a pseudo-first-order with a rate constant of 9.95 x 10(-3) min(-1). Finally, the application of this method was extended to real effluents. (C) 2016 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.