Evaluation of a low-phosphorus terpolymer as calcium scales inhibitor in cooling water

Abstract

AbstractScale formation, e.g. precipitation of calcium carbonate and calcium sulfate, is a significant problem in cooling water system. For the control of calcium scale and in response to environmental guidelines, the novel low-phosphorus terpolymer was prepared through free radical polymerization reaction of acrylic acid (AA), oxalic acid-allypolyethoxy carboxylate (APEM), and phosphorous acid (H3PO3) in water with redox system of hypophosphorous and ammonium persulfate as initiator. The synthesized AA–APEM–H3PO3 terpolymer was characterized by Fourier transform infrared spectrometer (FT-IR) and 1H NMR. The inhibition property of the low-phosphorus terpolymer towards CaCO3 and CaSO4 in the artificial cooling water was studied through static scale inhibition tests, and the effect on morphology of CaCO3 and CaSO4 was investigated with combination of scanning electron microscopy and X-ray powder diffraction analysis, respectively. FT-IR was also used to study the effect on morphology of CaCO3. It was shown ...