Synthesis Of A Terpolymer And Evaluation Of Its Scale Inhibition Performance

The development and utilization of high performance polymer scale inhibitors is a hot spot in the research of scale inhibitors.With acrylic acid(AA), maleic anhydride(MA) and hydroxyethyl methacrylate(HAMA) as the monomer, ammonium persulfate as the initiator,tertiary butyl alcohol as the molecular weight regulator, under the premise of economy and high efficiency,a novel terpolymer scale inhibitor was synthesized though aqueous radical polymerization. Through optimized the orthogonal experiment on factors affecting the scale properties of the copolymer,the optimal condition was determined. the optimum synthesis conditions of the copolymer monomer ratio(MA:AA:HEMA) was 1:1.5:0.3, triggered agent(monomer total quality) accounted for 12% and molecular weight modifier dosage(monomer total quality) was 8%, the reaction temperature was 95 ℃, reaction time was 4.5 hours,the copolymer had excellent scale inhibition performance, and the inhibition rate was 87%. The number average molecular weight of the copolymer was about 1259, which belongs to the polymer molecular of narrow transition zone.The copolymer was analyzed with infrared spectroscopy and scanning electron microscope, it containing carboxyl,ester, amide and sulfonic acid, and the specific surface area made dispersion and agglomeration inhibiting Ca CO3 precipitate easy.Lattice distortion and complex solubilizing a major role in suppressing precipitation copolymer mechanism. Through the comparative test on the scale inhibition performance about the terpolymer scale inhibitor and four green scale inhibitors, the influences of mass concentration of calcium ions, copolymer dosages and water temperatures on the scale inhibition performance were discussed.The results showed that, when the mass concentration of calcium ions were 480mg/L,the copolymer dosage were 3mg/L, the water temperature was 80℃, the scale inhibiting rate was 91.35%. The copolymer performance of calcium carbonate scale superior to conventional inhibitors, appropriate for the industrial circulating cooling water with high temperature and high hardness.Matrix removal evaluation and shakers culture were performed on the biodegradable performance.Which showed that the terpolymer was readily biodegradable material by terpolymer,the BOD5/CODcr value was 0.55, and the biodegradation rate increased extractives degradation rate to 75% in 28 days of the culture period.