Determination of molecular structure of kerogens using [sup 13]C NMR spectroscopy: I. The effects of variation in kerogen type

Journal Article · Thu Aug 01 04:00:00 EDT 1991 · Geochimica et Cosmochimica Acta; (United States)

DOI:https://doi.org/10.1016/0016-7037(91)90102-B· OSTI ID:7027267

Mann, A L; Patience, R L; Poplett, I J.F. ^[1]

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1. BP Research Centre, Sudbury-on-Thames (United Kingdom)

A 'carbon type' analysis for kerogens and coals based on solid state [sup 13]C NMR is reported here. Standard CP/MAS NMR spectra and dipolar dephased spectra are acquired. Chemical shifts of appropriate carbon types, stored in a computer-based reference library, are fitted to the dipolar dephased spectrum using computer software. This step is then repeated on the difference between the standard CP/MAS spectrum and the dipolar dephased spectrum. The method has been applied to a suite of eight immature kerogens and coals from sediments which vary from lacustrine, marine, to deltaic in origin, in order to investigate differences in molecular structure with variations in organic input. Distinct differences are observed in the distribution of oxygen-containing, aromatic and aliphatic carbon types depending on the type of organic matter contributing to the sediment (algal/bacterial or terrestrial) and the depositional setting. These differences are systematic and can be explained in the light of the chemical composition of the organic matter which originally contributed to the sediments.

• OSTI ID: 7027267
• Journal Information: Geochimica et Cosmochimica Acta; (United States), Journal Name: Geochimica et Cosmochimica Acta; (United States) Vol. 55:8; ISSN GCACAK; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010600* -- Coal
Lignite
& Peat-- Properties & Composition
02 PETROLEUM
023000 -- Petroleum-- Properties & Composition
BITUMINOUS MATERIALS
CARBON
CARBON 13
CARBON ISOTOPES
CARBONACEOUS MATERIALS
CHEMISTRY
COAL
ELEMENTS
ENERGY SOURCES
EVEN-ODD NUCLEI
FOSSIL FUELS
FUELS
GEOCHEMISTRY
ISOTOPES
KEROGEN
LIGHT NUCLEI
MAGNETIC RESONANCE
MATERIALS
MATTER
MOLECULAR STRUCTURE
NONMETALS
NUCLEAR MAGNETIC RESONANCE
NUCLEI
ORGANIC MATTER
RESONANCE
STABLE ISOTOPES
STRUCTURAL CHEMICAL ANALYSIS