English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/2606
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL | DATACITE
Exportar a otros formatos:


Control of the chemical structure of perhydrous coals. FTIR and Py-GC/MS investigations

AuthorsIglesias, María José; Río Andrade, José Carlos del ; Laggoun-Défarge, Fatima; Cuesta, María José; Suárez Ruiz, Isabel
Perhydrous vitrinites
Reflectance suppression
Chemical structure
Coal structure
Issue Date2002
CitationJournal of Analytical and Applied Pyrolysis 62 (2002) 1-34.
AbstractThis work analyses a set of perhydrous coals (mainly composed of huminite/vitrinite maceral group) in order to determine the inter-relations between the hydrogen content and the modifications in the coal structure at a molecular level. The study involves the direct solid state characterisation of the coal combined with the analysis of representative fragments of the coal network obtained through flash-pyrolysis. The perhydrous character of the coals is not reflected either in the aliphatic hydrogen concentration (from FTIR data) or by the presence of straight-chain aliphatic moieties in the pyrolysates. This structural study shows that perhydrous coals contain mainly aromatic structures with 1–2 rings and a very small concentration of aromatic rings of large size. In agreement with this, phenol and alkyl phenols are the most prominent degradation products whereas other aromatic compounds (mainly benzene and naphthalene derivatives) are minor and probably evaporative compounds. The major structural elements in the samples studied are simple phenols with a preponderance of substituted para alkyl. The results obtained show that the processes of hydrogen enrichment affect the reactions of aromatisation and condensation. During the natural evolution of the perhydrous coals the transformations of the oxygenated functionalities in the lignin precursor seem to have taken place without the parallel structural reorganisation of the lignin framework responsible for the formation of polycyclic aromatic systems. As a result, the chemical structure of perhydrous vitrinites in coals is substantially modified with respect to that described in ‘normal' coals. The results obtained also indicate that the source of hydrogen content and the effect that it has during the subsequent evolution process of the coals, affects the chemical structure of the perhydrous vitrinite and hence its properties and behaviour.
Publisher version (URL)http://dx.doi.org/10.1016/S0165-2370(00)00209-6
Appears in Collections:(INCAR) Artículos
(IRNAS) Artículos
Files in This Item:
File Description SizeFormat 
perhydrous.pdf537,64 kBAdobe PDFThumbnail
Show full item record
Review this work

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.