Containing Sulfonic Acid Polymer Scale Inhibitor Synthesis And Its Properties

The synthesis and antiscale performance as well as synthetic properties of the polymeric scale inhibitors containing sulfonic acid group are studied. Effects of reacting conditions and changes of water quality on the inhibition of the polymeric scale inhibitors are also discussed. The macromoleculars are characterized by IR spectra and TG, DTA.The water-soluble polymers are prepared by solution polymerization techniques with water as solvent and persulfate (NHOzSlOg as initiator. The monomers are maleic anhydride(MA), sodium allysulfonate(SAS), acrylic acid(AA), and acrylamide(AM) and such three inhibitors are obtained as MA-SAS, MA-SAS-AM, and AA-SAS. The effects of the monomer ratio, initiator amount, pH value of the reaction system, reaction temperature and reaction time and chain transfer agent on the synthesis and antiscale abilities are investigated. The results prove that the optimum synthetic conditions of MA-SAS are as follows: n(MA):n(SAS)=l:l, m((NH4)2S2Og):m(MA+SAS)=10-15%, pH=4.0-5.0, reaction temperature 75-80, reaction time 4h. The synthetic conditions of MA-SAS-AM are as follows: n(MA):n(SAS):n(AM)=l :1:0.5-1:1:0.6, m((NH4)2S2O8):m(MA+SAS+AM)=9-12%, m(chain transfer agent):m(MA+SAS+AM)=2.0-5.0%, temperature 75-85TC, time 5h. And the optimum synthetic conditions of AA-SAS are as follows: n(AA):n(SAS)=3:l-4:l, m((NH4)2S2Og):m(AA+SAS)=6-8%, temperature 85-90, time 5h.The results of static scale control experiment show that the performance of MA-SAS is fairly good at inhibiting the deposition of CaCOs, CaSO4, Ca3(PO4)2 and zinc salt. The CaCO3 scale inhibitory rate of the terpolymer MA-SAS-AM is only 55.7%(dosage 16mg/L). But terpolymer has excellent properties of inhibiting CaSCU and Ca(PO)z and the scale inhibitory rate can be up to 90.0%(dosage 4mg/L) and 95.7%(dosage 12mg/L) respectively. Additionally, its capabilities of stabilizing Zn2+ and dispersing Fe2Os are quite well.The changes of water quality such as polyer concentration, Ca2+ concentration, pH valueand temperature bring great effect on the scale inhibitory rate. By increasing polymer amountand decreasing Ca2+ concentration, pH value and temperature, the antiscale performance ofthe polymers will be improved. The results show that MA-SAS is fit for conditions as follows:calcium concentration 160-240mg/L, pH value 8.0-9.0, water temperature 60-75. Thepolymer MA-SAS-AM still possesses good antiscale ability even at the conditions of severepH 8.5-10.0 and calcium concentration 150-250mg/L.