Abstracto

Biodegradation of Poly (aspartic acid-citric acid) Copolymers by Natural Bacteria from the Receiving Water System

Yuling ZHANG, Caixia ZHAO, Shaoxin KANG, Xiaodong LIU, Wei LI, Jiaolong WANG, Zhiguang HU, Jun GUO

Poly (aspartic acid-citric acid) copolymer (PAC) is a novel high efficient water-treatment agent, and whether it is biodegradable determines its application prospect in actual circulating cooling system. In this paper, the biodegradability of PAC was researched by natural bacterial from the receiving water of domestic sewage in circulating cooling system, and investigated by carbon dioxide evolution tests. The copolymer (PAC) was characterized by FTIR, 1H NMR and 13C NMR. The results showed that the degradation ratio of PAC on 10 days and 28 days respectively reached 28.05% and 79.73%, which indicated that PAC belonged to the biodegradable water treatment agent. With the increase in the addition ratio of citric acid in copolymerization process and the decrease in the molecular weight of copolymer, the biodegradability of PAC was significantly enhanced. Cu2+ could decrease the degradation rate through inhibiting enzymatic activities. In addition, compared with other commercial scale inhibitors, biodegradable property of PAC was excellent.