Radiochemical neutron-activation analysis of sulphide ores using zinc diethyldithiocarbamate as extraction reagent

Abstract

A procedure for the analysis of lead sulphide and mixed sulphide ores for silver, arsenic, gold, cadmium, copper, manganese, antimony and zinc was developed with emphasis on the determination of the low gold to silver and arsenic to antimony ratios. Radiochemical neutron-activation analysis was necessary and a solvent-extraction technique has been developed. In the first separation step arsenic(III) chloride was extracted from the ore solution with benzene. The results are compared with the values obtained after separation of arsenic by distillation.

Gold(III), silver(I), copper(II), cadmium(II) and several other trace elements were extracted with zinc diethyldithiocarbamate in chloroform, whereas antimony(V) remained in the aqueous phase. The activities of the samples were counted on a germanium(lithium) well-type detector and compared with those of known volumes of standard solutions. Chemical yields were determined by re-activation.

The combination of conventional arsenic separation and this newly developed diethyldithiocarbamate extraction technique proved to be a very efficient and reliable method for the analysis of sulphide ores.