Aspects of the molecular structure of a bituminous vitrinite. Nuclear magnetic resonance study of the effects of imbibed pyridine

✍ Scribed by Wesley A. Barton; Leo J. Lynch; David S. Webster

• Publisher: Elsevier Science
• Year: 1984
• Tongue: English
• Weight: 938 KB
• Volume: 63
• Category: Article
• ISSN: 0016-2361
• DOI: 10.1016/0016-2361(84)90435-6

✦ Synopsis

The effects of imbibed pyridine on the molecular structure of a high-volatile bituminous vitrinite have been studied at room temperature by proton nuclear magnetic resonance pulse techniques. Both the free induction decay and nominal solid echo signals, recorded before and after addition of fully-deuterated and non-deuterated pyridine, could be decomposed into two or three components corresponding to protons with different degrees of mobility. The results confirm that pyridine produces substantial mobilization of the bituminous coal structure, thereby indicating the role of polar interactions in determining the molecular conformation of the coal. Analysis of the data indicates that two mobile proton populations can be distingyished in the presence of deuterated pyridine. Evidence is provided for strong coupling between protons and free-radical unpaired electrons in the vitrinite and for a reduction in this interaction due to the mobilizing and swelling effects of imbibed pyridine.