Carboxylate Functionalized Chitosan/Bentonite Composite Matrix as a Cation Exchanger for the Removal of Pb(II) From Aqueous Media: Kinetic and Equilibrium Studies

A novel composite matrix polymethacrylic acid-grafted Chitosan/Bentonite (PMAA-g-CS/B) was prepared through graft copolymerization reaction of methacrylic acid and chitosan in the presence of bentonite and N,N’- methylene-bisacrylamide as cross linker. The composite was well characterized using FTIR, XPS, SEM, TG/DTG, surface area analyzer and potentiometric titrations. The adsorption behavior of the composite towards Pb(II) from water and simulated battery manufacturing wastewater was studied under varying operating conditions. The kinetics of adsorption as well as adsorption isotherms at different temperatures was studied. Adsorption-desorption experiments over four cycles illustrate the feasibility of the repeated uses of this composite for the extraction of Pb(II) from aqueous solutions.