Flocculation mechanism by a novel combined aluminum-ferrous-starch flocculant (CAFS).
A combined flocculant (CAFS) was prepared with Al(2)(SO(4))(3)·18H(2)O, FeSO(4)·7H(2)O and starch. The flocculation mechanism of reactive brilliant red X-3B was studied. The results showed that CAFS was a cationic polymeric flocculant with high charge density, and its mesh starch chains grafted polyaluminum and polyferrous. At the preliminary stage, the main flocculation mechanism was adsorption and charge neutralization. At a later stage, the high molecular weight and flexible linear chains of CAFS initiated bridge-aggregation and sweep-flocculation. Moreover, the zeta potential and dynamic changes of flocs were closely related to flocculant dosages and the pH. The optimum dosage of CAFS and pH value were 0.990 mg/L and 5.0. Taken together, these results suggested CAFS as a novel flocculant in water treatment, with good results for the studied conditions.
Faculty of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, China. qintlin@163.com
Qintie
Q
Lin
Hanping
H
Pan
Haoping
H
Huang
Guoguang
G
Liu
Guangcai
G
Yin
D000535:Aluminum / Q000737:chemistry*; D005296:Ferrous Compounds / Q000737:chemistry*; D005427:Flocculation; D006863:Hydrogen-Ion Concentration; D013213:Starch / Q000737:chemistry*
D005296:Ferrous Compounds; D013213:Starch; D000535:Aluminum