Study On New Flocculants By Inverse Emulsion Polymerization And Its Performance

In this paper, there are two copolymers named P(AM/4-MASA) and P(AA/4-MASA) were synthesized through inverse emulsion polymerization used acrylamide(AM),acrylic acid(AA) and 4-methacrylamidosalicylic acid(4-MASA) as monomers. The paper investigates the effect of polymeric technology of P(AM/4-MASA) on viscosity-average molecular weight by univariate experiment, and use the same technology synthesize P(AA/4-MASA). Composition and structure of the copolymers was characterized by infrared spectroscopy and particle size analysis. It was used red mud slurry of Luo yang Heung Kong Aluminum Co.Ltd as studying object, systematically studied the effect of synthetic flocculants P(AM/4-MASA) to red mud flocculent separation, and contrasted with P(AM/4-MASA),P(AA/4-MASA) and PAA. The experiment date of P(AM/4-MASA) matched with PAA can used to analysis the effect of functional groups and molecular weight on flocculent ability.Through the univariate experiment, we know that the monomer ratio of AM(or AA) to 4-MASA is 27:1, concentration of initiator(ammonium persulfate) is 0.8%, emulsifier(Span-80,Tween-80) is 8%, HLB is 6.5, the oil-water ratio is 1.3:1, reaction temperature is 60℃.In this condition, the viscosity-average molecular weight of polymer reached to 1.3 million. The final adding amount of flocculants is 50g/t dry red mud. Through settling experiment, we know that as the proportion of 4-MASA in polymer declining and the molecular weight increasing, the settling rate of red mud is increase. When the monomer ratio of AM to 4-MASA is 23:1, the molecular weight is 1.15 million, the absorbency is 0.103. The overflow liquor clarity is close to foreign effective flocculants. In settling experiment, the settling rate of PAA is faster than P(AA/4-MASA),so the primary factor of settling rate is the molecular weight of flocculants. After P(AM/4-MASA) matched with PAA as 2:1, the stratified time is 79 seconds, the settling rate is 10.4 mm/min in 10 minutes and the absorbency is 0.105. The settling rate is close to PAA, and the overflow liquor clarity is close to P(AM/4-MASA).