Comparative study of the sequential methodologies for fractionation analysis of mercury in coal allonge with proximate and ultimate analysis

Abstract

In this work, BCR-sequential methods were used for the fractionation analysis of mercury in coal. Extraction methodologies BCR-SM, SSM and SS-UM were designed for fractionation analysis. The SSM and SS-UM are easy methods in term of operational time 36 h and 2 h respectively, from 51 h operational time of BCR-SM. Validations of applied methods were carried out by using SRM-1635A and spiking method to fractionation analysis of mercury in coal. Extraction efficiency of total mercury by pseudo method was checked by SRM-1635A, and obtained 97.1%. Total mercury was obtained 0.60–2.34 µg g− 1 in coal of four different coal seams from block-VII of Thar coalfield. Meanwhile, mercury level was decreased with increased depths it may be mineralogical composition changes. The highest mercury level was obtained in 200–203 m depth while the lowest was obtained in 152–154 m depth. Concentration of mercury in fractions was observed in the range of (32–60, 1.72–4.92, 9.58–50.8) %age with respectively in the acid-soluble, reducible and oxidizable fractions. Proximate, ultimate, and elemental analyses were also performed and Elemental Analyzer, respectively. The Cold Vapor Atomic Absorption Spectrometry was used to measure extracted fractional concentration of mercury in coal.