Synthesis And Application Of Cationic Polyacrylamide Flocculants

Since the reform and open policy,our country industry has obtained a high-speed development,but in the development industry process,we do not take the environment protection,making the pollution of the environment of the our country more and more serious. With the comprehensive implementation of sustainable development strategy and improvement of people's living level, people pay more attention to environment protection and life quality. Dealing with polluted water was attached more importance gradually.Cationic polyacrylamide is a ramification of polyacrylamide,and a cationic macromolecule flocculant of excellent effect to deal with waste water.Because of the peculiar side chain structure and high density charge,it is suitable for dealing with waste water which involves finegranular suspended matter,organics and colloid etc.At the present time most of cationic polyacrylamide flocculants were synthesized by Mannich reaction in China.,but CPAM obtained by this technology have many disadvantages,such as incomplete reaction,low cation degree and stability,short effective time and more byproduct. But cationic polyacrylamide flocculants were synthesized by copolymerization,has high molecule weight, high cation degree and stability. So in this article,a series of cationic polyacrylamide was produced by copolymerization in water solution.In this article, cationic polyacrylamide flocculants CPAM was produced with different cationic monomer and acrylamide(AM) through oxidentive-reductive and complex initiated system. Mass percent of monomer, amount of initiator, content of cation monomer, pH, reaction time et al on the effect of intrinsic viscosity of polymer were discussed as well as structure was analysed by IR(Infrared) spectroscopy. The results indicated that the performance of cationic polyacrylamide flocculants made by complex initiated system was superior to that made by oxidentive-reductive initiated system. The mechanism of copolymerization and the effect of factor on the molecular weight of cationic polyacrylamide flocculants was studied preliminary. Cationic polyacrylamide flocculants made by complex initiated system was applied to polluted water from the waste water factory in Shi Yan city, and the effects of the dosage of P(DMC-AM) and the pH value of wastewater on the removal rates of COD_cr, turbidity of wastewater were studied.The results of experiments showed that the best condition of flocculant P(DMC-AM) was dosage 8mg/L,the removal rates of COD_cr was above 80%,the removal rate of turbidity were all above 95% when the pH value of wastewater was 7.5.So cationic polyacrylamide flocculants P(DMC-AM) was a kind of excellent flocculant.