Abstract
High volatile bituminous coal was demineralized by a chemical method. The vibrations of the “aromatics” structure of graphite, crystalline or non-crystalline, were observed in the spectra at the 1600 cm−1 region. The band at 1477 cm−1 is assigned as VR band, the band at 1392 cm−1 as VL band and the band at 1540 cm−1 as GR band. Graphite structure remains after chemical leaching liberates oxygenated functional groups and mineral groups. The silicate bands between 1010 and 1100 cm−1 are active in the infrared (IR) spectrum but inactive in the Raman spectrum. Absorption arising from C-H stretching in alkenes occurs in the region of 3000 to 2840 cm−1. Raman bands because of symmetric stretch of water molecules were also observed in the spectrum at 3250 cm−1 and 3450 cm−1. Scanning electron microscopy analysis revealed the presence of a graphite layer on the surface. Leaching of the sample with hydrofluoric acid decreases the mineral phase and increases the carbon content. The ash content is reduced by 84.5wt% with leaching from its initial value by mainly removing aluminum and silicate containing minerals.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
F. Tuinstra and J.L. Koenig, Raman spectrum of graphite, J. Chem. Phys., 53(1970), p.1126.
R.A. Friedel and G.L. Carlson, Difficult carbonaceous materials and their infra-red and Raman spectra: reassignment for coal spectra, Fuel, 51(1972), p.194
Y. Wang, D.C. Alsmeyer, and R.L. McCreery, Raman spectroscopy of carbon materials: structural basis of observed spectra, Chem. Mater., 2(1990), p.557.
B. Manoj and A.G. Kunjomana, FT-Raman spectroscopic study of Indian bituminous and sub-bituminous coal, Asian J. Mater. Sci., 2(2010), No.4, p.204.
B. Manoj and A.G. Kunjomana, Chemical solubilization of coal using HF and characterization of products by FTIR, FT Raman, SEM and elemental analysis, J. Miner. Mater. Charact. Eng., 9(2010), No.10, p.919.
X. Li., J.I. Hayashi, and C.Z. Li, FT-Raman spectroscopic study of the evolution of char structure during the pyrolysis of a Victorian brown coal, Fuel. 85(2006), p.1700.
J. Robertson, Diamond-like amorphous carbon, Mater. Sci. Eng. R, 37(2002), p.129.
A. Georgakopoulos, A. Iordanidis, and V. Kapina, Study of low rank Greek coals using FTIR spectroscopy, Energy Sources, 25(2003), p.995.
Z.H. Wu and K.M. Steel, Demineralization of a UK bituminous coal using HF and ferric ions, Fuel, 86(2007), p.2194.
F. Rubiera, A. Arenillas, B. Arias, J.J. Pis, I. Suárez-Ruiz, K.M. Steel, and J.W. Patrick, Combustion behaviour of ultra clean coal obtained by chemical demineralization, Fuel, 82(2003), p.2145.
D.N. Shooto and E.D. Dikio, Morphological characterization of soot from the combustion of candle wax, Int. J. Electrochem. Sci., 6(2011), p.1269.
O.O. Sonibare, T. Haeger, and S.F. Foley, Structural characterization of Nigerian coals by X-ray diffraction, Raman and IR spectroscopy, Energy, 35(2010), p.5347.
W. Geng, T. Nakajima, H. Takanashi, and A. Ohki. Analysis of carboxyl group in coal aromaticity by Fourier transform infrared (FT-IR) spectrometry, Fuel, 88(2009), p.139.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Manoj, B., Kunjomana, A.G. Chemical leaching of an Indian bituminous coal and characterization of the products by vibrational spectroscopic techniques. Int J Miner Metall Mater 19, 279–283 (2012). https://doi.org/10.1007/s12613-012-0551-0
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12613-012-0551-0