Adsorption of chromium and zinc ions from aqueous solutions by cellulosic graft copolymers

Cellulosic graft copolymers were prepared by the reaction of bast ®bers of the kenaf plant (Hibiscus cannabinus) with acrylonitrile and methacrylonitrile monomers in aqueous media initiated by the ceric ion-toluene redox pair. The cellulose-polyacrylonitrile (Cell- PAN) and cellulose-polymethacrylonitrile (Cell-PMAN) graft copolymers were used for the removal of Zn(II) and Cr(III) ions from aqueous solutions at 30°C. Zn(II) ion was more sorbed than Cr(III) ion by both copolymers by an average factor of 1.80 ‹0.40. For each metal ion, the Cell-PAN graft copolymer was a more e€ective sorbent than the Cell-PMAN derivative. The amount of ion sorbed decreased with an increase in percentage graft and over the range 38±149% of the graft the amounts of Zn(II) and Cr(III) ions sorbed by Cell-PAN decreased by 44% and 56%, respectively.