Low-phosphorus maleic acid and sodium p-styrenesulfonate copolymer as calcium carbonate scale inhibitor

Abstract

In this article, a multifunctional and environment-friendly agent for industry circulation cooling water, maleic acid and sodium ρ- styrenesulfonate copoly-mer containing low-phosphorus was synthesized in aqueous solution with hypophosphorous acid/hydrogen peroxide as redox initiators. The effects of monomer feed ratio, temperature, dose of hypophosphorous acid, and drop speed of hydrogen peroxide on calcium carbonate inhibition were investigated, and the experimental conditions were optimized using orthogonal method. The composition and structure of the copolymer were analyzed by enery-dispersive X-ray analysis, fourier transform infrared spectroscopy, and nuclear magnetic resonance spec troscopy. The results of the static scale inhibition tests showed that the copolymer was effective in inhibiting the formation of calcium carbonate scale. The calcium carbonate precipitates formed in the static tests were examined by scanning electronic microscopy and X-ray diffraction spectra. The results indicate that in the presence of the co-polymer the calcium carbonate precipitate is the mixture of calcite and vaterite that could be stabilized kinetically in the presence of the copolymer. © 2009 Wiley Periodicals, Inc.