Synthesis of TiO2@ Activated Bagasse Fly Ash Nanocomposite as a Photocatalyst for Removal of Dyes and Heavy Metals from Wastewater

Abstract

TiO2@activated bagasse fly ash nanocomposite (TiO2/ABFA) was prepared and used as a photocatalyst for cadmium and methyl orange dye removal from bi-component pollutant solutions. Various weight ratios of TiO2 to ABFA (1:3, 1:2, and 1:1) were synthesized. Three systems were applied, the first system (A) was carried out under UV irradiation for 4 h and 1h in the dark, the second system (B) was carried out under UV irradiation with 100 µL H2O2 for 4 h and 1 h in the dark, and third system (C) was carried out in the dark for 5 h (only adsorption process). The characterization of ABFA and TiO2/ABFA were studied by SEM, XRF, and XRD patterns. The results showed that the highest MO and Cd2+ removal efficiency confirmed by TiO2/ABFA (1:2) nanocomposite photocatalyst. The application of TiO2/ABFA (1:2) nanocomposite compared to ABFA adsorbent led to enhancement of MO removal efficiency from 74.14 to 98.5% and from 55.28 to 82% at low and high MO concentration, respectively. Degradation of MO by system (B) was more effective than that by systems (A) and (C), while Cd2+ removal efficiency was higher by adsorption system (C). The optimum operation factors for mixed cadmium and methyl orange removal by TiO2/ABFA (1:2) were solution pH 7, 2 g/l catalyst dose, 300 min contact time, under UV irradiation and H2O2. Removal rate of MO and Cd2+ followed pseudo-second order model.