Elimination of reagent blank problems in the fire-assay pre-concentration of the platinum group elements and gold with a nickel sulphide bead of less than one gram mass

Abstract

Fire assay is a classical method used for the separation of platinum group elements and gold (PGE + Au) by pre-concentration with a collector. In the nickel sulphide fire assay, nickel and sulphur are used for the collection of PGE + Au. We have successfully reduced the mass of the collectors used without affecting element recovery. The PGE + Au are recovered from 25 g of SARM-7 reference material with only 0.5 g of nickel, compared with the 10 g proposed by other workers. The inherent blank problem due to impurities in the reagents is eliminated when the mass of nickel is reduced by the factor of 20 proposed.