Zero field and 2D NMR methods: Applications to fossil fuels

Conference · Tue Apr 01 04:00:00 EST 1986 · Am. Chem. Soc., Div. Gas Fuel Chem., Prepr.; (United States)

OSTI ID:5651898

Zilm, K W; Webb, G G

Over the last decade the development of spectroscopic methods suitable for nondestructively analyzing the structures of whole coals in the solid state has increased. The two most useful techniques to emerge so far have been Fourier transform infrared spectroscopy and carbon-13 solid state nuclear magnetic resonance. The latter technique in the form of the combination of cross polarization and magic angle sample spinning (CP/MAS) spectroscopy has proven the most useful in characterizing the functionalities present in the organic portion of coals. This method provides the best direct measure of carbon aromaticities and can also measure the relative amounts of protonated versus nonprotonated carbon when combined with dipolar dephasing techniques. Much more information is, in principle, contained in carbon-13 CP/MAS spectra, but the resolution typically obtained does not permit as detailed an analysis as is possible in the NMR of liquids. The situation for coal CP/MAS spectra is similar to that found in the NMR of complex biomolecules where the large number of resonances and broad natural linewidths result in incompletely resolved spectra. In solution studies these difficulties can often be overcome by the application of two dimensional (2D) NMR methods. In 2D NMR experiments a complex spectrum is separated into component subspectra on the basis of a second spectroscopic parameter. The subspectra are simpler, more resolved and thus easier to interpret.

• Research Organization: Dept. of Chemistry, Yale Univ., 225 Prospect Street, New Haven, CT
• OSTI ID: 5651898
• Report Number(s): CONF-860425-
• Conference Information: Journal Name: Am. Chem. Soc., Div. Gas Fuel Chem., Prepr.; (United States) Journal Volume: 31:1
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010600* -- Coal
Lignite
& Peat-- Properties & Composition
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400103 -- Radiometric & Radiochemical Procedures-- (-1987)
AROMATICS
CARBON
CARBON 13
CARBON ISOTOPES
CARBONACEOUS MATERIALS
CHEMICAL FEEDSTOCKS
COAL
COAL LIQUIDS
DATA ANALYSIS
ELEMENTS
ENERGY SOURCES
EVEN-ODD NUCLEI
FLUIDS
FOSSIL FUELS
FOURIER TRANSFORM SPECTROMETERS
FUELS
INFRARED SPECTRA
ISOTOPES
LIGHT NUCLEI
LINE WIDTHS
LIQUIDS
MAGNETIC RESONANCE
MATERIALS
MEASURING INSTRUMENTS
NMR SPECTRA
NONMETALS
NUCLEAR MAGNETIC RESONANCE
NUCLEI
ORGANIC COMPOUNDS
POLARIZATION
RESOLUTION
RESONANCE
SPECTRA
SPECTROMETERS
STABLE ISOTOPES
STRUCTURAL CHEMICAL ANALYSIS