Chemically Modified Lagenaria vulgaris as a Biosorbent for the Removal of CuII from Water

The ability of a biosorbent based on a chemically modified Lagenaria vulgaris shell for Cu-II ion removal from aqueous solution was studied in batch conditions. The biosorbent was characterized by Fourier-transform infrared spectroscopy and the effect of relevant parameters such as contact time, pH, biomass dosage, and initial metal ion concentration was evaluated. The sorption process was found to be fast, attaining equilibrium within 40 min, and results were found to be best fitted by a pseudo-second order kinetic model. Experimental data showed that the biosorption is highly pH dependent, and the optimal pH was 5.0. Results were analyzed in terms of the following adsorption isotherms: Langmuir, Freundlich, Temkin, and Flory-Huggins, by a linear regression method. The Cu-II biosorption followed the Langmuir isotherm model (r(2) = 0.998) with the maximum sorption capacity of 14.95 mg g(-1). The methyl-sulfonated Lagenaria vulgaris biomass investigated in this study exhibited a high potential for the removal of Cu-II from aqueous solution.