Water-insoluble carboxyl-containing starch graft polymer(carboxyl-containing starch) was prepared by grafting acrylonitrile onto highly cross-linked starch, followed by base saponifi-cation to convert nitrile group into a mixture of carboxamide and carboxylate groups. Ceric ammonium nitrate was used as initiator for the graft polymerization. The sorption kinetic properties of carboxyl-containing starch for several heavy metal ions have also been studied systematically. It is shown that the sorption rate of ...