A green and simple glow-discharge electrolysis plasma (GDEP) technique was used to synthesize the chitosan/ attapulgite/poly(acrylic acid-co-2-acrylamido-2-methyl-1-propanesulfonic acid) (CS/ATP/P(AA-co-AMPS)) microporous polymer. The results showed that the optimum pH for the adsorption of Pb2+, Cd2+, Co2+, and Cu2+ is 4.8, and time of adsorption equilibrium is 60 min. Adsorption kinetics fits well to the pseudo-second-order model. The maximum adsorption capacities for Pb2+, Cd2+, Cu2+ and Co2+ are 500.0, 301.7, 180.0 and 151.7 mg g-1, respectively. The microporous polymer has higher adsorption selectivity toward Pb2+ with the coexistence of Cd2+, Co2+, and Cu2+. The CS/ATP/P(AAco-AMPS) possesses promising regeneration and reusability using 2.0 g L-1 ethylenediamine tetraacetic acid tetrasodiumsalt (EDTA-4Na) solution as eluent. CS/ATP/P(AA-co-AMPS) can be used as a very promising absorbent for the separation, purification and selective recovery of Pb2+ in aqueous solution containing Cd2+, Co2+, and Cu2+ ions.
Keywords: chitosan; attapulgite; microporous polymer; adsorption selectivity; reusability