IUPAC > Gold Book > alphabetical index > C > coalification
icon

IndexesDownload


coalification

A geological process of formation of materials with increasing content of the element carbon from organic materials that occurs in a first, biological stage into peats, followed by a gradual transformation into coal by action of moderate temperature (about 500 K) and high pressure in a geochemical stage.
Note:
Coalification is a dehydrogenation process with a reaction rate slower by many orders of magnitude than that of carbonization. Some specific reactions approach completion before others have started. The dehydrogenation remains incomplete. The degree of coalification reached by an organic material in the process of coalification increases progressively and can be defined by means of the measured C/H ratio and of the residual contents of oxygen, sulfur and nitrogen.
Source:
PAC, 1995, 67, 473 (Recommended terminology for the description of carbon as a solid (IUPAC Recommendations 1995)) on page 485
Interactive Link Maps
First LevelSecond LevelThird Level
GraphGraphGraph
Cite as:
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. doi:10.1351/goldbook.
Last update: 2014-02-24; version: 2.3.3.
DOI of this term: doi:10.1351/goldbook.C01120.
Original PDF version: http://www.iupac.org/goldbook/C01120.pdf. The PDF version is out of date and is provided for reference purposes only. For some entries, the PDF version may be unavailable.
Current PDF version | Version for print | History of this term
picture