ICP-MS Determination of Silver and Platinum Group Elements in Copper Smelting Slag Tailings

The sample (0.400 0 g) was placed into a 50 mL sample tube. HCl-HNO₃-H₂O (3+1+4) mixed solution (10 mL) and 1.0 mL of saturated ammonium hydrogen fluoride solution were added, and the mixture was digested in a graphite digestor by ramp temperature rise. After cooling for 10 min, water was added to the digested solution to make its volume up to 50 mL. An aliquot of 10.0 mL was taken, and diluted to 20 mL with water. The solution was used for ICP-MS determination of Ag and platinum group elements (Ru, Rh, Pd, Ir, Pt, Au). The standard addition method was used to correct the matrix effect in preparation of standard curves. Values of detection limits (3s) found for 7 elements were in the range of 0.01-0.80 μg·L^-1. Test for recovery was made by standard addition method, giving results in the range of 94.0%-105%, with RSDs (n=11) ranged from 0.70% to 2.1%. The sample of copper smelting slag tailings was analyzed by the proposed method, giving results in consistency with those by graphite furnace atomic absorption spectrometry (FAAS).