A Comparative Study on the Removal of Cr(VI) using Fire Clay-TiO2 Nanocomposite and Fire Clay

The present study was aimed at investigating the adsorption behaviour of Cr(VI) ions onto fire clay -TiO2 nanocomposite (NC) and fire clay (FC). The effect of several parameters such as adsorbent dose, contact time, initial concentration, pH and temperature has been studied. The adsorption followed pseudo second order, Elovich kinetic models. Intraparticle diffusion model has also been attempted. The adsorption of Cr(VI) was found to be maximum in the pH range 8-11. Adsorption on both clay and nanocomposite obey Langmuir and Freundlich models. The thermodynamic parameters �Gº, �Hº, �Sº have also been evaluated. Adsorptions on both clay and nanocomposite were found to be endothermic and chemisorptive in nature. Chromium removal was better with nanocomposite than with clay.