| A novel environmentally friendly multifunctional scale and corrosion inhibitorcontaining carboxylic acid, sulphonic acid and phosphonic acid groups was synthesizedfrom the monomers of itaconic acid (IA), sodium allysulfonate (SAS) and sodiumhypophosphite (SHP) by oxidation-reduction initiator system. The influences of reactiontemperature, reaction time, NaH2PO2amount and monomer composition on the scaleinhibition efficiency were discussed. The optimum synthetic conditions were determined byorthogonal experiments. The structure of the copolymer was characterized by the means ofinfrared spectroscopy and elementary analysis.The performances of scale and corrosion inhibition, dispersion and biodegradability ofthe IA/SAS/SHP copolymer were studied. The results showed that the IA/SAS/SHPcopolymer has good performances of scale and corrosion inhibition, dispersionperformance on ferric oxide and biodegradability. When the concentration of IA/SAS/SHPcopolymer was20mg·L-1, the static scale inhibition rate on CaCO3was92.6%. When theconcentration of IA/SAS/SHP copolymer was1.5mg·L-1, the dynamic scale inhibition rateon CaCO3could reach above90%. When the IA/SAS/SHP copolymer dosage was28mg·L-1, the static scale inhibition efficiency on Ca3(PO4)2could achieve100%. theIA/SAS/SHP copolymer has good dispersion capacity for ferric oxide. When theconcentration of IA/SAS/SHP copolymer was30mg·L-1, the transmittance was only65.7%.When the concentration of the IA/SAS/SHP copolymer was60mg·L-1, the corrosion ratewas0.02823mm·a-1and the corrosion inhibition rate reaches above90%. According to theanalysis of Tafel polarization curves，the IA/SAS/SHP copolymer predominantly act asanodic inhibitor. In addition,69.5%of the copolymer could be biodegraded within28days,which indicates that the copolymer is an environmentally friendly product.The synergistic scale inhibition performance between the IA/SAS/SHP copolymer andelectrostatic water treatment or magnetic water treatment was investigated by the dynamicfouling monitor equipment. The results showed that the scale inhibition rate ofIA/SAS/SHP in the presence of electrostatic field could increase by16.65%and the scaleinhibition rate of IA/SAS/SHP in the presence of magnetic field could increase by9.76%.The scale inhibition rate of the IA/SAS/SHP copolymer when both magnetic field and electric field existing could reach100%.The CaCO3scale sample were observed and analyzed by SEM and XRD. Thecooperative formation mechanism of the IA/SAS/SHP copolymer，electrostatic field andmagnetic field was discussed, which could provide the theoretical guidance for thedevelopment of chemical-physical coordination water treatment. |
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