Synthesis And Flocculation Property Of Amphoteric Polyacylamide Inverse Emulsion

Flocculant is the important water treatment material, and the key basis of flocculating method using for water treatment technology. Now, the research on flocculant is aiming to high-efficiency, low consumption, safe and no secondary pollution, so such targets has long been the key point of flocculating research. Amphoteric acrylamide (APAM) is a kind of soluble polymer with special molecular structure.Compared with cationic acrylamide and anionic acrylamide, it has advantages of the above mentioned PAM. Additionally, APAM has such merits as anti-polyelectrolyte and wide pH range. They were used for the treatment of wastewater and they were also widely used in the petroleum and paper industries and for environment protection protection.Under this background, amphoteric flocculants were synthesized by performing inverse emulsion copolymerization.The anion polyacrylamide (PAM) inverse emulsion was prepared by the copolymerization of acrylamide (AM) with2-acrylamido-2-methyl propylsulfonic acid (AMPS) via inverse emulsion polymerization. A series of amphoteric polyacrylamides (APAM) of difference molecular weight were prepared by a subsequent Mannich reaction. Several factors affecting synthesizing of PAM were discussed; infrared spectrum were applied to analyze the structure of synthesized amphoteric PAM. The main conclusions are as the follows:the appropriate synthesize technology of anion polyacrylamide:ammonium persulfate and Sodium bisulfite are0.3%and0.4%respectively, concentration of monomer is42.5%, reaction temperature is about60℃, PH equals7.0, the molecular weight of reacting product is1.3×10And that time, it could be conclude that the optimum conditions of the product included1:1:1.2of molar ratio for PAM, HCHO and (CH3)2NH,35-40℃of reaction temperature,4h of the reaction time, and6.0of the reaction pH value in the Mannich reaction. The emulsion stability of the obtained product is good.The result of infrared spectrum analysis showed that APAM had Sulfonic acid, quaternary ammonium and amido groups, which were the characteristic radicals of the amphoteric polyacrylamide. The APAM were applied to basic fuchsin simulating the decoloring of wastewater directly using the inverse emulsion. The effects of the mole ratios of AMPS/PAM and HCHO/PAM, concentration of APAM and pH value were studied. The results showed that the decolorization efficiency of APAM was higher than the anion or cation polyacrylamides. An ideal decolorization with basic fuchsin could be obtained under the following conditions:PAM/formaldehyde/dimethylamine mole ratio was1/0.5/0.6. the concentration of APAM was600mgL-1and pH value was6.0.The results of flocculation experiment showed that APAM had satisfactory flocculation performance to2per thousand diatomite wastewater comparing to nonionic polyacrylamide emulsion and anionic polyacrylamide emulsion. And at the following conditions:the acrylamide/formaldehyde/dimethylamine ratio was1/1/1.2, the AMPS/AM ratio was0.1, and pH value was3.0-8.0, the flocculation performance of APAM was excellent, and sedimentation rate reached100%especially pH value was5.0.