Synthesis and performance evaluation of cationic flocculants modified from starch

Key words:  starch  diallyldimethyl ammonium chloride  flocculant  acrylamide

Abstract:

Cationic graft copolymers of soluble starch were synthesized by using acrylamide and diallydimethyl ammonium chloride (DADMAC) as monomer, and (NH⁺₄ )2S208/NaHS03 as initiator. Through orthogonal experiments, the optimal conditions of starch grafted PAM were confirmed，then a series of cationic flocculants modified from starch were synthesized by introducing cationic monomer DADMAC, Flocculation abilities were examined in dealing with Daqing ASP flooding wastewater. The results show that Daqing ASP flooding wastewater should be treated in neutral or weak acid condition, with suitable pH value between 6,0 and 7.0. When the mass ratio of monomer to soluble starch is 1: 9, cationic flocculant performs well. When the concentration is 50 mg L"1, light transmittance reaches 95% ,oil, polymer and suspended solid contents accord with national standards.