Application of response surface methodology for the photo degradation of dye using ZnO nanorods loaded on the activated carbon

In this work, ZnO with a nanorod morphology loaded on activated carbon (ZnO NRs-AC) was synthesized using the co-precipitation method for the photo-degradation of malachite green (MG) under the UV light. The photo-catalyst was characterized using various analytical techniques including XRD and FE-SEM. The Box-Behnken design (BBD) combined with the response surface methodology (RSM) was applied for the optimization of the influential parameters. The optimum values for the parameters involved were as follow: photo-catalyst dosage,16 mg; MG concentration, 30 mg L-1; and reaction time was 46 min. Studying the effect of foreign ions on the performance of the photo-catalytic process indicated the stability of ZnO NRs-AC in the photo-catalytic degradation of MG. According to the Langmuir–Hinshelwood (L–H) kinetic model, the kinetic degradation of MG followed a pseudo-first order kinetic model.