Functionalized hybrid material precursor to chitosan in the efficient remediation of aqueous solutions contaminated with As(V)

Chitosan is grafted with 3-aminopropyltriethoxysilane under inert atmosphere in acetic acid–ethanol solvent mixture. The materials are characterized by the SEM-EDX and FT-IR analyses. The successful grafting of silane with chitosan is confirmed by the EDX and FT-IR analytical data. The hybrid material is then employed in the remediation of aqueous solutions contaminated with As(V) under batch and column reactor operations. The sorption capacity of chitosan is tremendously increased with the incorporation of 3-aminopropyltriethoxysilane and the hybrid material showed high percent removal of As(V) within the pH ranges between pH 3.0–7.0. The equilibrium sorption is achieved within 120 min of contact and the kinetic data is best fitted to the pseudo first order kinetic model. Moreover, high percentage removal of As(V) is observed in a wide concentration range and the concentration dependence data fitted well to the Freundlich adsorption isotherm. On increasing the background electrolyte (NaNO3) concentration by 100 times decreased significantly the removal of As(V); however, the presence of co-existing ions could not significantly affect the removal of As(V) using the synthesized hybrid material. Furthermore, the loading capacity of As(V) under the dynamic conditions using hybrid material packed column is estimated and found to be 2.576 mg/g.