Capability of cationic water-soluble polymers in conjunction with ultrafiltration membranes to remove arsenate ions

Arsenic is one of the most hazardous pollutants, and is present in water, mainly, as As(V) and As(III), and in its inorganic hydrolysis species. Great efforts have been made to develop effective removal techniques. One alternative is the use of water-soluble polymers containing functional groups to remove these toxic species. This paper presents the synthesis and characterization (FT-IR and H-1 NMR spectroscopy, as well as thermo-gravimetry TG-DSC) of two cationic water-soluble polymers containing tetra alkylammonium groups, poly[2(acryloyloxy)ethyl]trimethylammonium chloride, and poly [2-acryloyloxy)ethyl]trimethylammonium methyl sulfate (P(SAETA)). The arsenate retention properties were investigated using the liquid-phase polymer-based retention technique. The polymer structure and the exchangeable anions' nature have been shown to be two important variables in the removal efficiency of arsenate anions from aqueous solutions. Both investigated polymers were found to efficiently remove HAsO42- species from an aqueous media, with pH ranging from 6 to 8. The exchange of methyl sulfate for the chloride anion on P(SAETA) improved arsenate ion retention ability. The modification of ionic strength by Na2SO4 addition induced a significant decrease in the cationic polymer's arsenate retention properties. The polymers' retention properties were not studied using real samples.