Palladium nitrate—magnesium nitrate modifier for electrothermal atomic absorption spectrometry. Part 3. Determination of mercury in environmental standard reference materials

Abstract

A single addition of 15 µg of palladium is sufficient for 40–60 determinations of mercury if the graphite tube is not heated to temperatures higher than 1500 °C in the cleaning step. A pyrolysis temperature of 400 °C can be used without any loss of mercury, and a characteristic mass of 0.1 ng of mercury was obtained for an atomization temperature of 1000 °C. Interferences caused by high sodium chloride concentrations could be eliminated by using a mixture of 95% argon and 5% hydrogen as the purge gas. Mercury could be determined accurately in Aquatic Plant, Albacore Tuna, River Sediment and Coal Fly Ash reference materials.