Separation Science and Technology, Vol.41, No.14, 3123-3139, 2006
Electron beam grafted polymer adsorbent for removal of heavy metal ion from aqueous solution
An electron beam grafted adsorbent was synthesized by post irradiation grafting of acrylonitrile (AN) on to a non-woven thermally bonded polypropylene ( PP) sheet using 2 MeV electron beam accelerator. The grafted poly(acrylonitrile) chains were chemically modified to convert a nitrile group to an amidoxime (AMO) group, a chelating group responsible for metal ion uptake from an aqueous solution. The effect of various experimental variables viz. dose, dose rate, temperature, and solvent composition on the grafting extent was investigated. PP grafted with the amidoxime group (AMO-g-PP) was tested for its suitability as an adsorbent for removal of heavy metal ions such as Co2+, Ni2+, Mn2+, and Cd2+ from aqueous solution. Langmuir and Freundlich adsorption models were used to investigate the type of adsorption of these ions. The adsorption capacities of the adsorbent for the metal ions were found to follow the order Cd2+ > Co2+ > Ni2+ > Mn2+. The kinetics of adsorption of these ions indicated that the rate of adsorption of Cd2+ was faster than that of other ions studied.