Decolourisation of textile dye effluent using kaolin calcium carbonate titanium dioxide composites optimisation using statistical and ann approach

Abstract

Rising incidents of pollution caused by textile industries because of azo based dyes used on various textile materials puts a continuous stress on effluent treatment plants. Dyes have high tinctorial values and thus even 1 ppm of dyes in the effluent is visible to naked eyes and prevents the penetration of sunlight leading to deterioration of biodiversity within water bodies. Dyes have also been found to release toxic amines, making water bodies at high risk and hence treatment of dye effluents has become one of the important effluent treatment processes over the years. Recent studies on dye effluents using Advanced Oxidation Processes (AOPs) have provided promising outcomes in dye-effluents treatment. AOPs have the capabilities of oxidizing organic and inorganic compounds by generation of strong oxidizing agents and hydroxyl radical (OH ). UV-Photolysis using Titanium dioxide (TiO2) produces hydroxyl radical (OH ) by UV irradiation and is found to be popular among AOPs commercially due to its cost, non-toxic nature and commercial availability. Studies show that the quantum yield of TiO2 responsible for oxidation and reduction of contaminants, are low and thus certain modifications can aid improving the decolourising performance. Current study focuses on producing an adsorbent-cum photocatalyst, a composite material made of kaolin (Al2Si2O5(OH)4), calcium carbonate (CaCO3) and titanium dioxide (TiO2), using calcination technique with optimum surface morphology that can facilitate both adsorption and photocatalytic reaction for enhanced colour removal. newline