Isothermal decomposition of Colorado oil shale

Technical Report · Wed May 01 04:00:00 EDT 1985

OSTI ID:6890824

Miknis, F P; Conn, P J; Turner, T F

Isothermal decomposition studies have been conducted in the temperature range of 368 to 500/sup 0/C using a 52-gallon-per-ton Colorado oil shale. A tubular and a heated sand-bath reactor system were used, both yielding material balances of at least 99.7 +- 0.2%. Kerogen conversion to bitumen, oil, gas, and solid product was measured for different residence times at isothermal conditions. Elemental analyses were obtained on the bitumen, oil, and solid reaction products. Product gas composition was measured using an on-line gas chromatograph. Liquid and solid state /sup 13/C NMR measurements were made to determine the aliphatic and aromatic carbon fractions in the liquid and solid products. Molecular weights of the bitumens and oils were measured also. The hydrogen to carbon ratios, carbon aromaticities, and molecular weights of the produced oils were remarkably constant at all temperatures and residence times. The bitumen showed compositional changes indicative of progressive aromatization during decomposition. The aliphatic carbon in the residue decreased, having a time dependence similar to the total organic carbon, whereas the aromatic carbon exhibited almost no time dependence. The total aromatic carbon in the products increased by about 30% over the original aromatic carbon in the raw shale. One set of experiments showed a 94% conversion of kerogen to total soluble products. Rate constants for the kerogen decomposition and product evolution were obtained by simple first-order, distributed activation energy, and initial slope methods of analyses. Attempts were not successful in modeling the kerogen decomposition using a bitumen intermediate. While good fits were obtained for the oil and gas data, the model did not provide satisfactory fits to the bitumen or residue data. The lack of fit to the bitumen data is attributed to the changing composition of the bitumen. 27 refs., 21 figs., 3 tabs.

• Research Organization: Western Research Inst., Laramie, WY (USA)
• DOE Contract Number: FC21-83FE60177
• OSTI ID: 6890824
• Report Number(s): DOE/FE/60177-2288; ON: DE87009043
• Country of Publication: United States
• Language: English

Related Subjects

04 OIL SHALES AND TAR SANDS
040402* -- Oil Shales & Tar Sands-- Surface Methods
040500 -- Oil Shales & Tar Sands-- Properties & Composition
ACTIVATION ENERGY
BITUMENS
BITUMINOUS MATERIALS
CARBON 13
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON ISOTOPES
CARBON MONOXIDE
CARBON OXIDES
CARBONACEOUS MATERIALS
CHALCOGENIDES
CHEMICAL COMPOSITION
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
CHEMICAL REACTORS
CHROMATOGRAPHY
DATA
DECOMPOSITION
ENERGY
ENERGY SOURCES
EVEN-ODD NUCLEI
EXPERIMENTAL DATA
FISCHER ASSAY
FLUIDS
FOSSIL FUELS
FUELS
GAS ANALYSIS
GAS CHROMATOGRAPHY
GASES
HIGH TEMPERATURE
HYDROCARBONS
INFORMATION
ISOTOPES
KEROGEN
KINETICS
LIGHT NUCLEI
MAGNETIC RESONANCE
MATERIAL BALANCE
MATERIALS
MINERAL OILS
MOLECULAR WEIGHT
NMR SPECTRA
NUCLEAR MAGNETIC RESONANCE
NUCLEI
NUMERICAL DATA
OIL SHALES
OILS
ORGANIC COMPOUNDS
ORGANIC MATTER
OTHER ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PYROLYSIS
REACTION KINETICS
RESIDUES
RESONANCE
SEPARATION PROCESSES
SHALE OIL
SPECTRA
STABLE ISOTOPES
TAR
THERMOCHEMICAL PROCESSES
TIME DEPENDENCE
YIELDS