Effect of functionalization on the adsorption capacity of cellulose for the removal of methyl violet.

In this research paper a comparative study has been carried out for the removal of methyl violet dye using unfunctionalized and functionalized cellulose. The functionalization was achieved through esterification of cellulose with furan-2,5-dione. The functionalization of the cellulose was evidenced using BET, FT-IR, SEM and TGA. The adsorption isotherm data was fitted using different isotherm models like Langmuir, Freundlich, Temkin, Flory-Huggins and Dubinin-Kaganer-Radushkevich models and found to follow Langmuir and Temkin isotherm models with high value of correlation coefficients. Functionalized cellulose (106.38 mg g(-1)) showed higher dye removal capability than unfunctionalized cellulose (43.668 mg g(-1)). The kinetics of adsorption was investigated using pseudo first order, second order, Elovich, liquid film diffusion and intra-particle diffusion models. The mechanism of adsorption was found to follow pseudo second order rate equation. Thermodynamic studies showed that the adsorption process was endothermic and spontaneous.