Determination of mercury in coal by non-oxidative pyrolysis and cold vapour atomic-fluorescence spectrometry

Abstract
Mercury was liberated from coal by non-oxidative pyrolysis at 800 °C with a nitrogen purge and collected in acidified potassium permanganate solution. Subsequent determination was by cold vapour atomic-fluorescence spectrometry using an argon-sheathed windowless cell. The mercury vapour was generated continuously by pumping tin(II) chloride and sample to a novel reduction cell. This continuous flow system offered excellent precision, with a 2% relative standard deviation at 0.5 ng ml–1 and a detection limit (2σ) of 0.043 ng ml–1. The accuracy and precision were assessed by performing replicate analyses on a number of coals, including NBS SRM 1632a bituminous coal, for which a mean value of 134 ng g–1 and a standard deviation of 3.1 ng g–1 were obtained. The excellent sensitivity, precision and extended linear working range of the method (5 ng g–1 to 25 µg g–1) are noted.

This publication has 0 references indexed in Scilit: