Effect of Ionic Strength on the Adsorption of Pb~(2+) and Cu~(2+) onto Bentonite / Sodium Lignosulfonate Graft-Polymerized with Acrylamide and Maleic Anhydride

Adsorbent composites comprising of bentonite / sodium lignosulfonate graft-polymerized with acrylamide and maleic anhydride( BLPAMA) were prepared and used to investigate the effect of ionic strength on the adsorption of Pb2 +or Cu2 +onto BLPAMA in single or binary metal ion solutions,the adsorption isotherms,kinetics and thermodynamics of Pb2 +and Cu2 +onto BLPAMA with or without addition of0. 2 mol / L Na NO3 in the binary metal ion solutions. The results show that the increase of ionic strength leads the adsorption capacity of Pb2 +or Cu2 +to decrease in the single metal ion solution,the adsorption capacity of Pb2 +to decrease while the adsorption capacity of Cu2 +to increase in the binary metal ion solution.