Application of Raman Spectroscopy in Coal Research: A Case Study on Tatapani-Ramkola Coal

Abstract

Coal, an organic sedimentary rock derived through the coalification of ancient plant material, is a vital fossil fuel with extensive industrial applications. The maturity of its organic matter is a crucial indicator of thermal evolution and rank, which governs the physicochemical properties of coal and its potential suitability for various applications. Raman spectroscopy has emerged as a powerful and non-destructive analytical tool in coal studies, offering insights into structural and chemical properties of carbonaceous rocks. This technique is particularly effective in assessing coal rank and maturity of organic matter, as well as identifying microstructural changes during the pyrolysis process, which is critical for enhancing its application in energy production and other fields. This study examines the application of Raman spectroscopy in assessing coal maturity by analyzing the spectral characteristics of coal samples from the Tatapani-Ramkola coalfield in Chhattisgarh, India. Raman spectroscopy of Tatapani-Ramkola coal reveals broad ‘D’ (1348-1394 cm-1) and ‘G’ (1579-1591 cm-1) bands with low ID/IG ratios (0.30-0.58), indicating moderate maturity. The G-D band separation (176-239 cm-1) reflects the transformation of aliphatic structures into aromatic rings. FWHM (D band) values (153.52-224.01 cm-1) classify the coal samples as medium-rank sub-bituminous coal. © 2025 Geological Society of India, Bengaluru, India.