A NOVEL AND EFFICIENT PHOTOCATALYSIS (ZnO/BENTONITE) FOR DISINFECTION OF Escherichia coli AND Pseudomonas aeruginosa UNDER VISIBLE LIGHT IRRADIATION

Abstract

n the present study, a new composite catalyst which highly active under the visible light was synthesized by immobilizing onto bentonite surface using ZnO materials (ZnO/Bent). For this, a simple in situ participant technique was used. The samples were characterized using SEM, XRD, BET techniques. SEM images possess that ZnO particles have nearly a spherical structure. Bentonite clay was used to increase the surface area of the samples. The obtained BET surface area of the samples shows that the ZnO/Bent catalyst was lower than that of pure Bentonite. The aim of this study was to evaluate the effectiveness of photocatalytic disinfection with ZnO-Bent composite against Escherichia coli and Pseudomonas aeruginosa under visible light. The obtained results show that when E. coli strain was subjected to ZnO-Bent mediated photocatalytic disinfection under solar irradiation, more than 98 % disinfection of the targeted E. coli was achieved within 2 hours and also 100% of P. aeruginosa colonies were inactivated within 4 hours under solar irradiation. A Possible degradation mechanism for ZnO/Bent composite was proposed in this study.