Synthesis, flocculation and adsorption performance of amphoteric starch

A novel amphoteric copolymer flocculant was synthesized by incorporating a cationic moiety 2,3-epoxypropyl trimethyl ammonium chloride (GTA) and an anion moiety phosphate onto the backbone of starch with microwave radiation. The synthesized starch copolymer was characterized and examined by FTIR, H-1 NMR spectroscopy, scanning electron microscopy (SEM), molecular mass and polydispersity, swelling power and solubility index. Flocculation performance was evaluated in 50 mg/L methyl violet solution. It has been found that these flocculation characteristics mainly depended on the charge neutralization, followed by the interchain bridging of the amphoteric copolymer. Also, adsorption to Pb (II) solution was investigated by jar test. The results showed that the adsorption capacity of amphoteric copolymer correlated with pH value, adsorption time and initial Pb (II) concentration. (C) 2012 Elsevier Ltd. All rights reserved.