Chemical variations in coal macerals separated by density gradient centrifugation

✍ Scribed by Gary R. Dyrkacz; C.A.A. Bloomquist; Ljiljana Ruscic

• Publisher: Elsevier Science
• Year: 1984
• Tongue: English
• Weight: 957 KB
• Volume: 63
• Category: Article
• ISSN: 0016-2361
• DOI: 10.1016/0016-2361(84)90206-0

✦ Synopsis

Using density gradient centrifugation, 22 coals with varying maceral composition and rank have been separated. The carbon, hydrogen and nitrogen contents of selected density fractions have also been obtained for each coal. Examination of the data shows that the density gradient procedure provides information not only on the differences between maceral groups, but also within maceral groups. In general, as density increases the H-C ratio was found to decrease across each maceral group density band. Although more variable, the O-C ratio tended to increase across the maceral bands. In addition, the aromaticity and ring index calculated from the data show that, for many coals, both parameters increase through a given maceral distribution. From the data, it has been concluded that density gradient centrifugation can provide a more detailed insight into the nature of coal and coal macerals.