LONG-TERM STABILITY OF A MIXED PALLADIUM IRIDIUM TRAPPING REAGENT FOR INSITU HYDRIDE TRAPPING WITHIN A GRAPHITE ELECTROTHERMAL ATOMIZER

For hydride trapping and atomization in a graphite electrothermal atomizer the treatment of a pyrolytic graphite coated electrographite tube with a single, manual application of a mixed trapping reagent of 50 mug of palladium and 50 mug of iridium allows up to 300 complete trapping and atomization cycles. Precision is generally better than 3% and the efficiency of trapping is virtually 100% for As, Se and Bi. The application of this mixed palladium-iridium trapping reagent improves the routine use of this technique and considerably simplifies the hardware and software requirements to provide a fully automatic system.