Amidoximated cellulose as scavenger for cadmium and nickel cations

The aim of the present work concerns the adsorption of Cd(II) and Ni(II) onto amidoximated cellulose from aqueous solution, as previously studied for other metals. Characterization of this modified cellulose is further performed using TGA, DSC and 13 C NMR. The rate of ions' removal increases with pH, initial concentration of metal, contact time and temperature. The maximum adsorption capacities of Cd(II) and Ni(II) are 3.58 and respectively 1.8 mmol, per gram of adsorbent. The formation of 1/1 and 2/1 complexes with Cd(II) and respectively Ni(II) is proved by the adsorption limit values of these metal ions. The adsorbed metals are easily desorbed from the amidoxime cellulose by stirring with an ethylenediaminetetraacetic solution, and recycling of the support is tested in view of its potential use as a cation exchanger.