Optimization of photocatalytic process parameters for the degradation of acrylonitrile using Box Behnken Design

Abstract

The present study involves the photocatalytic degradation of aqueous solution of acrylonitrile (ACN) which was carried out in a batch reactor under UV light. The degradation efficiency was evaluated with ZnO as a photocatalyst and hydrogen peroxide as an oxidant for a period of 5 h. The variables examined in this study included ZnO dose (0.5–3.0 g/L), pH (2–12), and H2O2 concentration (2.5–10 m mol/L). The rate of degradation was studied in terms of changes in concentration of the pollutant using spectrophotometry. The optimal values of operational parameters leading to degradation of ACN were obtained using Box Behnken design (BBD) under response surface methodology (RSM). The optimum conditions were found to be ZnO dose of 1.48 g/L; pH 7.0 and hydrogen peroxide (H2O2) concentration of 4.22 m mol/L. Under optimum condition, the degradation efficiency of ACN was found to be 89.6%. Optimization of photocatalytic process parameters for the degradation of ACN by BBD under RSM effectively copes with interaction between optimizing variables and its prediction agreed well with the experimental result.