Efficiency evaluation of photocatalytic process using ZnO nano catalyst for removal of 2,4,6-trichlorophenol by response surface methodology

Abstract Backgroundandpurpose:Chlorophenols are one of the toxic compounds in the industries that are resistant to biodegradation and they last a long time in environment. Therefore, it is necessary to eliminate them and prevent pollution of the receiving waters. The aim of this study was evaluation of ZnO nano-particles for removal of 2,4,6-trichlorophenol from aqueous solution based on the response surface methodology (RSM) model. Materials and methods: Effect of independent variables including pH, catalyst dose, contact time and the initial concentration of 2,4,6-trichlorophenol on response variable (removal of 2,4,6-trichlorophenolfrom) were evaluated based on the response surface methodology (box-behnken method). In this study, all experiments were carried out in a batch reactor containing ZnO nano-particles under 15 Watt UV lamp Results:The results showed that the best conditions for the removal of 2,4,6-trichlorophenolwere achieved at pH= 3,nano-particle concentration 0.4g/l, reaction time and74.72 min and initial concentration of 2,4,6-trichlorophenol50 mg/l contact time (95.85% removal efficiency). Results: The results showed that the best conditions for removal of 2,4,6-trichlorophenol were achieved at pH=3, nano-particle concentration 0.4g/l, reaction time 74.72 min, initial concentration of 2,4,6-trichlorophenol 50 mg/l (95.85% removal efficiency). Conclusion: The results showed that photocatalytic process was accelerated in the presence of ZnO nano-particle and enhanced removal of 2,4,6-trichlorophenol.