The adsorption equilibrium, kinetics, and thermodynamics of removal of copper, zinc, cadmium, and lead from aqueous solutions by a grafted starch polyacrylonitrile composite polymer were investigated with respect to time, temperature, pH, and metal ion concentration. The polymer exhibits greater affinity towards copper rather than zinc, lead and cadmium with an uptake rate of 0.06 ppm (Cu2+) min–1 mg–1, 0.033 ppm (Zn2+) min–1 mg–1, 0.02 ppm mg–1 (Pb2+) and 0.015 ppm mg–1 (Cd2+). Uptake rates and capacity for all the metals investigated decreased with increasing pH. The adsorption was described by a Langmuir-type isotherm. The percentage metal ions removed was directly proportional to adsorbent dosage. Selected mass transfer and kinetic models were applied to the experimental data to examine uptake mechanism. The boundary layer and intra-particle diffusion played important roles in the adsorption mechanisms of copper and zinc and the kinetics followed a pseudo-second order kinetic model. Regeneration studies showed a 5% reduction in metal uptake capacity over three adsorption–desorption cycles when exposed to metal ion concentration of 250 ppm for all metals investigated.

Kinetics and thermodynamics of heavy metal removal from water using starch polyacrylonitrile composite polymer

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.