Alternative Composite Nanosorbents Based on Turkish Perlite for the Removal of Cr(VI) from Aqueous Solution

New nanocomposite sorbents were synthesized and used for Cr(VI) removal from aqueous solution by modifying Turkish perlite with alpha-MnO2 (PAM) and gamma-Fe2O3 (PGI) nanoparticles. Nanocomposite sorbents were characterized using scanning electron microscopy (SEM) and FTIR. The effects of several parameters such as contact time, amount of sorbent, pH, and concentration were investigated and it was found that the sorption capacity for Cr(VI) was found to be highly pH dependent. Also the experimental data were evaluated in terms of different isotherm models. The data of PGI were well fit to DR isotherm model whereas PAM data were well described with Temkin isotherm model. The sorption capacities were found to be 8.64 and 7.6 mg g(-1) for PGI and PAM, respectively. This confirms that these nanocomposites retain the constituent nanoparticle properties while being macroscopic particles suitable for chromium removal in water treatment.