Studies On The Preparation Of Natural Polymer Modified Flocculant And Its Application

Water pollution is a general and serious problem in the world. Sewage treatment is a effective way and a necessary mean to solve water shortage and environmental pollution. Flocculant can remove 80-90% of SS snd 65-95% of colloid in the water effectively, then further disinfection of water easier. Compared with the traditional flocculant, bioflocculant have the characteristics such as high efficiency, non-toxic, easily biodegradable, no secondary pollution and widely used, it is a kind of environment-friendly flocculant. Starch graft polyacrylamide andβ-cyclodextrin graft polyacrylamide are new natural polymer flocculant. It has been widely applied in food, chemical, and medical industries etc.The optimal synthesis conditions of starch graft polyacrylamide andβ-cyclodextrin graft polyacrylamide were studied in this paper. Discuss the influence of react conditions to monomers conversion ratio, graft percentage and graft efficiency. Then use the starch graft polyacrylamide to treat wastewater of Wei-river. Use theβ-cyclodextrin graft polyacrylamide to removal of copper from wastewater. The following were the results.In the synthesis process of starch graft polyacrylamide, high graft percentage were that the mass ratio of starch and acrylamide is 1:4, reaction time is 5h, reaction temperature is 60℃, the mass fraction of initiator in acrylamide is 0.1%; high monomers conversion ratio were that the mass ratio of starch and acrylamide is 1:4, reaction time is 6h, reaction temperature is 70℃, the mass fraction of initiator in acrylamide is 0.1%; high graft efficiency were that the mass ratio of starch and acrylamide is 1:4, reaction time is 5h, reaction temperature is 60℃, the mass fraction of initiator in acrylamide is 0.1%。The best flocculation condition to treat wastewater of Wei-river:flocculating agent volume is 10ml, flocculation temperature 40℃, pH>9, the longer of the flocculating time the result is better. Use PAM,St-PAM,Al2(SO4)3 and Al2(SO4)3\St-PAM to treat wastewater of Wei-river and the results were:the Al2(SO4)3\St-PAM is the best, then St-PAM, but Al2(SO4)3 is the worst.In the synthesis process of starch graft polyacrylamide, high monomers conversion ratio and graft percentage were that the mass ratio of acrylamide andβ-CD-6-Ots is 4:3, the reaction time is 24h, reaction temperature 70℃, the distilled water volume is 160ml. The optimal conditions to removal of copper from wastewater is:the quality of flocculating agent is 2.5g, flocculating time is 1h, pH is 11, flocculation temperature 40℃.