Adsorption of hexavalent chromium (Cr(VI)) from wastewater using novel chitosan/halloysite clay nanocomposite films

Abstract

Nano composite films have been prepared in the laboratory by impregnating halloysitenanoclay on chitosan matrix. The functional groups present in the composite films have been investigated using Fourier transform infrared spectroscopy (FTIR) and morphological structure of the synthesized films are analysed using scanning electron microscopy (SEM). Thermo gravimetric analyser (TGA) is used for investigating the thermal stability of the composite. The films are used for adsorption of hexavalent chromium from wastewater. Optimum pH for adsorption is 3.0 and all other experiments are conducted at pH 3.0. It has been observed that adsorbent dosage required is very less when compared to pure chitosan as adsorbent. The adsorption capacity is also very high when compared with pure chitosan for removal of Cr (VI) under the same conditions. The equilibrium studies have been conducted and data is fitted to the Langmuir equation. The kinetic studies reveal that the adsorption mechanism is pseudo second order. The study shows that the chitosan/halloysite clay can be used as a promising adsorbent for hexavalent chromium uptake from wastewater