Comparison of an Advanced Mercury Analyzer with the Cold Vapor Atomic Absorption Technique for the Determination of Mercury in Coal

Dong Li, Western Kentucky University

Abstract

For over 30 years the industry standard method for mercury analysis has been the cold vapor atomic absorption spectrometric technique (CVAAS). Recent developments in improving this technique have focused on procedures for concentrating mercury in the analyte or materials to improve detection. The LECO Corporation produces an Advanced Mercury Analyzer, the AMA-254, for analysis of the solid and liquid samples. The system allows for the thermal heating of the sample to decompose the sample and release mercury, which is concentrated in a gold amalgam. Thermal desorption of the mercury from the amalgam is detected by atomic absorption spectroscopy. A comparison of the performance of the AMA-254 with CVAAS techniques was made using standard reference materials. The CVAAS method follows the procedure in ASTM Method D 3684. The results of this research indicate that the AMA-254 is very easy to use in the analysis of solid and liquid samples without pretreatment and has a lower detection limit than the CVAAS technique.