Photocatalytic Degradation of Alachlor on Fe-TiO2-Immobilized on GAC under Black Light Irradiation Using Box-Behnken Design

Abstract

The aim of this work was focused on the photocatalytic degradation of alachlor from aqueous solution using 10%wt Fe-TiO2, as 0.1%wt of Fe doped into TiO2 structure, immobilized on granular activated carbon (GAC) under black light irradiation. The extended photocatalytic conditions were studied as functions of catalyst loading, number of black light, and initial pH of solution using Response Surface Method (RSM) based on Box-Behnken design (BBD). Characterizations of the photocatalyst by TGA-DTA, and XRD were investigated. Photocatalyst was calcined at 400°C under nitrogen atmosphere. As a Result of calcinations, photocatalyst consisted of only graphite crystallite while the crystallite phases of TiO2 were not observed. The degradation results showed that the photocatalytic process gave the highest percent degradation comparing with adsorption and photolysis processes. The effects of three operating variables which are catalyst loading, number of black light, and initial pH of solution on the degradation efficiency of alachlor were examined. Photocatalyst loading was only significant parameter effecting for photocatalytic degradation of alachlor. The photocatalytic degradation slightly increased with increasing of number of black light while pH of solution did not affect photocatalytic degradation of alachlor. The photocatalytic process and adsorption process were affected from the initial alachlor concentrations as well.