Study On Synthesis And Application Of Polyene And Polyamines Groups Chelate Flocculant

As the development of society, the confliction between the need of high quality water and ongoing water pollution is being sharper and sharper, especially when heavy metal ions enter into the water which can hazard water sources, water lives, soil, crops and even the health of people. So it is urgent for us to treat polluted water. Among all the methods we have, the flocculant settling method is broadly used and proved to be economical and powerful. So the development of new effective flocculants is becoming more and more important.In this article, two kinds of macromolecular flocculants were successfully synthesized with polyacryamide as raw materials. Under certain pH value, CPAM, a kind of cationic macromolecular flocculants, was synthesized by grafting amido formaldehyde and triethylene tetramine to branches of polyacryamide. Under the same condition, APAM (a kind of anionic macromolecular flocculants) was prepared using diglycolamidic acid. Factors which will influence reactions, such as material ratio, reaction time, temperature, pH value etc. were evaluated to find an optimum condition for synthesis. Under the optimum condition, a stable product with Mw lager than 5 million was obtained.Three kinds of waste water containing heavy metal ions Hg²⁺, Pb²⁺, Cu²⁺ respectively were treated with flocculants synthesized and optimum conditions were investigated. Results show that the synthesized flocculants have a good flocculation effect particularly for water polluted by heavy metal ions. The reason is this kind of flocculant has special active groups which could chelate with heavy metal ions while other flocculants don't have.In addition, flocculation mechanism theory was also studied and it is shown that the mechanism is based on the caption of heavy metal ions by active groups, charge neutralization and adsorption bridging mechanism.