A water-insoluble polymeric oxidizing medium is contemplated that has a plurality of polymerized N-pyridinium vinylbenzyl triiodide or tribromide moieties whose pyridinium rings bear two substituents, R1 and R2, that are independently a hydrido or a C1-C4 alkyl group, and correspond in structure to the...http://www.google.es/patents/US7300587?utm_source=gb-gplus-sharePatente US7300587 - Oxidation of heavy metal ions
