Abstract:
BACKGROUNDLead-zinc ore often co-exists with sulfide ore to form polymetallic deposits. The content of the associated beneficial elements can provide an important reference for the comprehensive utilization evaluation of the mineral deposits. Using current methods, tungsten, molybdenum, tin, germanium, selenium, and tellurium were analyzed by grouping or separate melting and analytical methods with strong operation and low analysis efficiency were employed. Moreover, copper and lead with high content, and selenium with the content higher than 1 μg/g interferes with the determination of tungsten and tellurium, respectively, when using current methods.
OBJECTIVESTo establish a method for the determination of tungsten, molybdenum, tin, germanium, selenium, and tellurium in lead-zinc ore by ICP-MS.
METHODSThe samples were melted with sodium peroxide. After extraction, 0.8% citric acid solution was added to complex tungsten, molybdenum and tin to form metal complexes. 8-9 g cation resin was used to exchange sodium, copper, lead, zinc, iron and other major elements. The content of tungsten, molybdenum, tin, germanium, selenium and tellurium was determined by ICP-MS using a kinetic discrimination model with rhenium and boron as the internal standard.
RESULTSAfter the resin treatment, the removal rate of copper, lead, zinc and iron is higher than 96%, the actual concentrations in the measuring medium are 0.192 ng/mL-1.28 μg/mL, which effectively eliminates the interference of the main elements. The correlation coefficients of the working curve are 0.9994-0.9999, better than 0.9923-0.9992 before cation resin treatment. The method is verified by standard material, the relative errors are -8.33%-7.00%, the standard addition recoveries are 94.9%-107.5%, and the relative standard deviation (RSD, n=8) is less than 8%.
CONCLUSIONSThis method can be used effectively to separate the main interference elements from the solution by sample pretreatment, optimizing the measuring medium and determining the accurate and rapid values of multiple elements in lead-zinc ore.