Abstract: In order to synthesize a novel dithioamino starch xanthogenate (DSX), the acetalization reaction between soluble starch and trimethyl orthoacetate was carried out to form starch acetal-3,6 ring ester, followed by cross-linking in aqueous ammonia, graft copolymerization with acrylamide and sulfonation. Using orthogonal array design, the optimal reaction system was determined to consist of: 10 g of starch, 1.77 g of cross-linking reagent, 0.053 g of initiator, 3.37 g of graft monomer and 6.30 g of carbon disulfide. The synthesized product could remove 98.5% Cu2+ from simulated wastewater. Further, its structure was characterized by FT-IR, elemental analysis, nuclear magnetic resonance (13C-NMR and H-NMR), thermogravimetric analysis (TG) and scanning electron microscope (SEM).

Key words: starch, graft copolymerization, adsorption, metal ion, characterization