Maity, Sudip and Choudhury, Ashim (2008) Influence of Nitric Acid Treatment in Different Media on X-ray Structural Parameters of Coal. Energy & Fuel , 22 (6). pp. 4087-4091. ISSN 0887-0624

PDF Restricted to Registered users only Download (242Kb) | Request a copy

Abstract

The treatment of coal with nitric acid in aqueous and non-aqueous media introduces changes in the chemical and spatial structure of the organic mass. Four coals of different rank have been treated with nitric acid in aqueous and glacial acetic acid media for assessing the changes in the structural parameters by the X-ray diffraction (XRD) technique. Slow-scan XRD has been performed for the raw and treated coals, and X-ray structural parameters (d002, Lc, and Nc) and aromaticity (fa) have been determined by profile-fitting software. Considerable variation of the structural parameters has been observed with respect to the raw coals. The d002 values have decreased in aqueous medium but increased in acetic acid medium; however, Lc, Nc, and fa values have increased in aqueous medium but decreased in acetic acid medium. It is also observed that considerable oxidation takes place during nitric acid treatment in aqueous medium, but nitration is the predominant phenomenon in acetic acid medium. Disordering of the coal structure increases in acetic acid medium, but a reverse trend is observed in the aqueous medium. As a result, structurally modified coals (SMCs) are derived as new coal-derived substances.

Item Type:	Article
Subjects:	Power Coal
Divisions:	UNSPECIFIED
Depositing User:	Dr. Satyendra Kumar Singh
Date Deposited:	19 Nov 2011 09:28
Last Modified:	19 Nov 2011 09:28
URI:	http://cimfr.csircentral.net/id/eprint/56

Actions (login required)

View Item