Study About Fe-TiO2/AC and Co-TiO2/AC Composites Prepared from Waste Streams for an Efficient Removal and Photocatalytic Degradation of Cibacron Yellow F-4G Dye

Abstract

Kinetic and adsorption studies of CYF-4G onto the Co-TiO₂/AC and Fe-TiO₂/AC composites were performed considering its pH at point of zero charge (pH_PZC) and using batch and photocatalytic experimental set-ups under solar-simulated light. Activated carbon (AC) obtained from peanut shell remnants and TiO₂ photocatalyst electrochemically produced from titanium scrap and doped with Fe and Co, respectively, were used to create the Fe-TiO₂/AC and Co-TiO₂/AC composites. The ability of the Fe-TiO₂/AC and Co-TiO₂/AC composites to adsorb and photocatalyze the degradation of Cibacron Yellow F-4G (CYF-4G) from wastewater was investigated. Thermogravimetric (TGA), scanning electron microscopy (SEM), X-ray diffraction (XRD), a novel X-ray absorption technique (XRA), and elemental analysis were used to evaluate doped ACs (EA). Interesting relationships were found between SEM, XRA and TGA data and doped amount of catalyst on ACs. Optimal dye adsorption was found at a pH of 2.0. The CYF-4G adsorption kinetics are followed according to the pseudo-second order model. Langmuir model fitted the adsorption data the best. A decrease in adsorption capacity was observed when the catalyst dope percentage increased. A synergistic adsorption, removal and degradation efficiency of the dye close to 100% was achieved around 120 min. under simulated visible radiation.