Spectrofluorimetric study of some resinites from Indian coals and lignites

Abstract

Spectral fluorescence measurements were carried out on three common resinite types-with greenish-yellow, yellow, and orange fluorescence colours, from the Tertiary (Eocene) lignites of Matanomadh and Panandhro Lignite fields of Kutch and Permian (Lower Gondwana) coals from Raniganj Coalfield. The analysis revealed a distinct shift in their maximum fluorescence intensity (λ max.) towards higher wavelength and increase in red/green (650-500 nm) quotient (Q) corresponding with increase in the age of the deposit. The resinite types from Tertiary lignites show λ max. at500-510 nm for type-I, 520-530 nm for type-2 and 540 nm for type-3 with corresponding Q values of 0.17-0.29,0.38-0.49 and 0.69, respectively. Whereas, the Permian coals have λ max. at 580, 600 and 610 nm and Q values of 0.59, 1.47 and 1.9 respectively for greenish-yellow, yellow, and orange fluorescing resinite types.