Solvent extraction of selenium for its neutron activation determination incopper-nickel ores and their processed products

It was shown that the formation of organoselenium compounds affects the com pleteness of selenium extraction with aromatic, aliphatic, and unsaturated hydrocarbons. A unified solvent extraction-neutron activation method was de veloped for determining selenium in copper-nickel ores and their processed products. Three procedures of analysis were proposed for the determination of selenium alone and for the simultaneous determination of selenium with e ither arsenic or arsenic and antimony. The procedures involve extraction wi th toluene (or in the presence of 1-hexene) from sulfate (perchlorate)-brom ide (chloride) solutions. The accuracy of the method was verified by compar ing the results of analysis obtained for samples by the proposed and indepe ndent methods and by comparing the results obtained by the analysis of refe rence materials with the certified values. The detection limits for seleniu m, arsenic, and antimony were found equal to 0.005, 0.0002, and 0.0003 g/t, respectively. The values of RSD in the concentration range 0.01-400 g/t va ry from 27 to 3%.