Flocculation Behaviors of Collagen Protein-Al(III) Composite Flocculant

Abstract

Hydrolyzed collagen protein (HCP) was prepared by the hydrolysis of solid skin wastes, and then cross-linked with glycerol triglycidyl ether (GTE) to produce cross-linked collagen protein (CCP). By combination CCP with different amounts of Al2(SO4)3, a series of CCP-Al (III) composite flocculants (CCP-Al) were successfully synthesized. A kaolin suspension (5 g/L) was utilized as a model system to investigate the flocculation behaviors of the as-prepared flocculants. When the dosage of the CCP-Al was 50 mg/L, the flocculation extent reached 95% in 20 minutes with the sludge volume ratio lower than 15%. Under the same conditions, the CCP-Al exhibited better flocculation performance than the Al2(SO4)3. Scanning electron microscope (SEM) observations revealed that the size of flocs formed by CCP-Al was larger than that of Al2(SO4)3, suggesting a better aggregation of flocs.