High speed removal of toxic acid red dye using photocatalytic-hybrid composite material

About 40,000 synthetic dyes and pigments are utilized in different industries worldwide. This results in generation of huge volumes of effluents that are difficult to handle as dye removal is not an easy process and contaminates the environment severely. The present study first time reports the use of Cu impregnated TiO2 nano material combined with calcinized white stone waste to form a hybrid composite (W-Cu/TiO2) to remove acid red dye. The effect of various process parameters including pH, dose, initial concentration, and time was optimized during the present study. Various adsorption isotherms including Langmuir, Freundlich, DR, Harkin Jura, Temkin adsorption models and pseudo first order and pseudo second order kinetic models were fitted to results. The results indicated that neutral pH, low dosage, high concentration, and more contact time, enhanced the adsorption capacity of W-Cu/TiO2 nanocomposite. W-Cu/TiO2 removed acid red dye using a combination of adsorption and photocatalysis. This resulted in a high-speed removal of most of acid red dye from water within 15 min only. W-Cu/TiO2 SEM micrographs show that it has a regular nano-granular structure as compared to other materials.