Removal of arsenite by coupled electrocatalytic oxidation at polymer-ruthenium oxide nanocomposite and polymer-assisted liquid phase retention

Nanocomposite materials synthesized by incorporation of ruthenium oxide nanoparticles into a poly(pyrrole-alkylammonium) matrix have been characterized by transmission electron microscopy and by electrochemistry. Ruthenium oxide-based nanocomposites films coated onto carbon appeared efficient electrocatalysts for the oxidation of arsenic(III) into arsenic(V) species at a remarkable low potential, i.e. in the 0.3-0.5 V vs. Ag/AgCl range. Bulk electrocatalytic oxidation of arsenite solutions could be performed in the presence of a water-soluble poly(quaternary ammonium) salts acting as the supporting electrolyte and also as an As(V) complexing agent, which allowed to combine electrocatalytic oxidation of As(III) with the liquid phase polymer-assisted retention (LPR) technique to efficiently remove arsenic from polluted solutions. (C) 2012 Elsevier B.V. All rights reserved.