Production, separation and speciation of no-carrier-added Hgradionuclides using greener methodologies

摘要

Species dependent studies of no-carrier-added(nca) mercury were carried out using radioanalytical techniquecoupled with two greener analytical methodologies. The ad-sorption of nca ~(195m,g)Hgand ~(197m)Hgradionuclides on chitosanbiopolymer and cloud point extraction (CPE) was studied todevelop environmentally sustainable speciation methodologiesat ultra trace level. Species information was obtained bycomparing the adsorption profile of nca radiomercury onchitosan biopolymer with the software code CHEAQS PRO.Results obtained from the adsorption study were validatedby CPE technique using non ionic surfactant and mixedmicelle. Both the experiments established that nca Hg existedas Hg(II). The experimental results support the presence ofHgCl_2species over the pH range 2-4, whereas Hg(OH)_2isthe main species over the pH range 6-8. Chitosan biopolymerand mixed micelle [Triton-X-114 and cetyltrimethylammo-nium bromide (CTAB)] constitute an efficient reagent for thepreconcentration of ultra trace level mercury.