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High temperature ceramic membrane reactors for coal liquid upgrading

Description: In this project we intend to study a novel process concept, i.e, the use of ceramic membranes reactors in upgrading of coal derived liquids. Membrane reactors have been used in a number of catalytic reaction processes in order to overcome the limitations on conversion imposed by thermodynamic equilibrium. They have, furthermore, the inherent capability for combining reaction and separation in a single step. Thus they offer promise for improving and optimizing yield, selectivity and performance … more
Date: January 1, 1992
Creator: Tsotsis, T.T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrogen bonding in asphaltenes and coal. Progress report, March 1, 1977--August 31, 1977

Description: A calorimetric method is presented for the simultaneous evaluation of equilibrium constant, K, and molar enthalpy, ..delta..H/sup 0/, for 1 : 1 adduct formation of quinoline (Qu) with asphaltene (A), together with its acid/neutral (AA) fraction and its base (BA) fraction, isolated from a centrifuged liquid product (CLP) sample prepared from Kentucky hvAb coal at 27.6 MPa hydrogen pressure and 723K, with reactor charged with glass pellets. The same procedure was used to determine K and ..delta..… more
Date: August 1, 1977
Creator: Li, N. C. & Tewari, K. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High temperature ceramic membrane reactors for coal liquid upgrading

Description: In this project we will study a novel process concept, i.e., the use of ceramic membrane reactors in upgrading of coal model compounds and coal derived liquids. In general terms, the USC research team is responsible for constructing and operating the membrane reactor apparatus and for testing various inorganic membranes for the upgrading of coal derived asphaltenes and coal model compounds. The USC effort will involve the principal investigator of this project and two graduate research assistan… more
Date: January 1, 1992
Creator: Tsotsis, T.T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Heavy recycle solvent studies in two-stage coal liquefaction. Final technical report, September 1, 1982-December 30, 1983

Description: The objective of this program has been to study the chemistry of the components with high boiling points in a direct coal liquefaction recycle solvent and to identify those components which lead to higher overall yields and improved product stability in the initial coal dissolution step of direct coal liquefaction processes. The major conclusions are: -454 C recycle solvent is primarily aromatic hydrocarbons (73%) and contains almost no asphaltenes; +454 C recycle solvent is primarily asphalten… more
Date: January 10, 1984
Creator: Longanbach, J. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization of Oil and Gas Reservoir Heterogeneity

Description: The ultimate objective of this cooperative research project is to characterize Alaskan petroleum reservoirs in terms of their reserves, physical and chemical properties, geologic configuration in relation to lithofacies and structure, and development potential. The project has two tasks: Task 1 is a geological description of the reservoirs including petrophysical properties, i.e., porosity, permeability, permeability variation, formation depth, temperature, and net pay, facies changes and reser… more
Date: January 1, 1992
Creator: Sharma, G. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An sup 15 N NMR method for the characterization of organic sulfur in coal and coal products via iminosulfurane formation

Description: The indirect of organic sulfur by {sup 15}N NMR spectroscopy in the solid state is feasible by facile reactions providing the iminosulfurane structures. Unfortunately, nitrogen chemical shifts appear to be insufficiently sensitive to the nature of the sulfur substituent to be useful for structural studies. Further work is underway to determine the {sup 15}N chemical shifts of iminosulfuranes formed from dibenzothiophene, 4-4{prime}-dimethoxydiphenyl sulfide, and a sulfur-containing, methylated … more
Date: September 1, 1991
Creator: Franz, J. A.; Lamb, C. N. & Linehan, J. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chemistry and structure of coal-derived asphaltenes, Phase III. Quarterly progress report, July--September 1977

Description: The major benzene insoluble fraction, carboid, solvent-separated from Synthoil coal liquid, was found to be 90 wt.% soluble in pyridine. This fraction, which contains about 50% of the ash present in Synthoil coal liquid, could be 96% de-ashed by dissolution in pyridine. A hypothetical average structure for Synthoil asphaltene has been derived from analytical, VPO MW, x-ray, NMR and chemical functionality data. A self-association model has been developed for calculating molecular weights, and fr… more
Date: November 1, 1977
Creator: Yen, T. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Catalyst dispersion and activity under conditions of temperature-staged liquefaction

Description: The general objectives of this research are (1) to investigate the use of highly dispersed catalysts for the pretreatment of coal by mild hydrogenation, (2) to identify the active forms of the catalysts under reaction conditions and (3) to clarify the mechanisms of catalysis. The ultimate objective is to ascertain if mild catalytic hydrogenation resulting in very limited or no coal solubilization is an advantageous pretreatment for the transformation of coal into transportable fuels. The experi… more
Date: February 1, 1992
Creator: Davis, A.; Schobert, H.H.; Mitchell, G.D. & Artok, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Characterization of Oil and Gas Reservoir Heterogeneity

Description: The ultimate objective of this cooperative research project is to characterize Alaskan petroleum reservoirs in terms of their reserves, physical and chemical properties, geologic configuration in relation to lithofacies and structure, and development potential. The project has two tasks: Task 1 is a geological description of the reservoirs including petrophysical properties, i.e., porosity, permeability, permeability variation, formation depth, temperature, and net pay, facies changes and reser… more
Date: January 1, 1991
Creator: Sharma, G. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Catalyst dispersion and activity under conditions of temperature- staged liquefaction

Description: The general objectives of this research are (1) to investigate the use of highly dispersed catalysts for the pretreatment of coal by mild hydrogenation, (2) to identify the active forms of the catalysts under reaction conditions and (3) to clarify the mechanisms of catalysis. The ultimate objective is to ascertain if mild catalytic hydrogenation resulting in very limited or no coal solubilization is an advantageous pretreatment for the transformation of coal into transportable fuels. The experi… more
Date: September 1, 1991
Creator: Davis, A.; Schobert, H.H.; Mitchell, G.D. & Artok, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Characterization of Oil and Gas Reservoir Heterogeneity

Description: The objective of the cooperative research program is to characterize Alaskan reservoirs in terms of their reserves, physical and chemical properties, geologic configuration and structure, and the development potential. The tasks completed during this period include: (1) geologic reservoir description of Endicott Field; (2) petrographic characterization of core samples taken from selected stratigraphic horizons of the West Sak and Ugnu (Brookian) wells; (3) development of a polydispersed thermod… more
Date: January 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Characterization of Oil and Gas Reservoir Heterogeneity

Description: The ultimate objective of this cooperative research project is to characterize Alaskan petroleum reservoirs in terms of their reserves, physical and chemical properties, geologic configuration in relation to lithofacies and structure, and development potential. The project has two tasks: Task 1 is a geological description of the reservoirs including petrophysical properties, i.e., porosity, permeability, permeability variation, formation depth, temperature, and net pay, facies changes and reser… more
Date: January 1, 1991
Creator: Sharma, G. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Hydrotreating the bitumen-derived hydrocarbon liquid produced in a fluidized-bed pyrolysis reactor

Description: The pyrolysis of bitumen-impregnated sandstone produces three primary product streams: C{sub 1}-C{sub 4} hydrocarbons gases, a C{sub 5}{sup +} total liquid product, and a carbonaceous residue on the spent sand. The bitumen-derived hydrocarbon liquid was significantly upgraded relative to the native bitumen: it had a higher API gravity, lower Conradson carbon residue, asphaltene content, pour point and viscosity and a reduced distillation endpoint relative to the native bitumen. The elemental co… more
Date: January 1, 1991
Creator: Longstaff, D. C.; Deo, M. D.; Hanson, F. V.; Oblad, A. G. & Tsai, C. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Chemistry and structure of coal derived asphaltenes and preasphaltenes. Interim report

Description: It is the objective of this project to isolate the asphaltene and preasphaltene fractions from coal liquids from a number of liquefaction processes. These processes consist of in general: catalytic hydrogenation, staged pyrolysis and solvent refining. The asphaltene fractions may be further separated by both gradient elution through column chromatography, and molecular size distribution through gel permeation chromatography. These coal-derived asphaltene and preashpaltene fractions will then be… more
Date: January 1, 1979
Creator: Yen, T. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Chemistry and structure of coal derived asphaltenes and preasphaltenes. Quarterly progress report, October-December 1979

Description: The solvent refined coal liquid from the Pittsburg and Midway Coal Mining Company pilot plant located at Fort Lewis, Washington, has been received and separated reproducibly by the standard solvent fractionation method into three fractions. The coal liquid received is so-called stripper bottom product from SRC-II mode. Table I shows the coal liquefaction reaction conditions and the composition of the products. The 300 cc autoclave system equipped with injection loading, withdrawal systems, and … more
Date: January 1, 1979
Creator: Yen, T. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Chemistry and processability of crude oil asphaltenes as studied by ultracentrifugation

Description: From the number of crudes of this study, there appears to be a positive correlation between the total quantity of crude oil hetero atoms (S, N, Ni, and V) which are precipitated under conditions of ultracentrifugation and the degree of that particular crude's difficulty of hydroprocessing. Because of its powerful ability to separate colloidal material from suspensions and because of the known colloidal nature of asphaltenes, the ultracentrifuge was employed to effect the separation of crude oil… more
Date: January 1, 1980
Creator: Weeks, R. W., Jr. & McBride, W. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Hydrogen bonding in asphaltenes and coal. Quarterly report for April 1, 1979--June 30, 1979

Description: Structural analyses are reported of upgraded coal-liquids derived from catalytic hydroprocessing of a 30 to 70 blend SRC I with SRC II in a trickle bed reactor under different process conditions. The results indicate that along with the decrease in toluene insolubles, heteroatom (O,N,S) content, aromatic content and corresponding increase in aliphatic content, the hydrogen-bonded structure and phenolic OH content of the coal-liquid drastically decrease with increase in contact time and temperat… more
Date: July 16, 1979
Creator: Li, N. C.; Tewari, K. C. & Hara, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Hydrogen bonding in asphaltenes and coal. Quarterly report, October 1--December 31, 1978

Description: Solvent-refined coal, SRC II process solvent, prepared by Pittsburgh and Midway Coal Company from Kentucky No. 9 and No. 14 blend bituminous coal, has been separated into acid/neutral and base fractions. Viscosity, infrared, and proton magnetic resonance studies are reported on the SRC II (before fractionation), and its acid/neutral fraction, and on the interaction of these coal-liquids with quinoline and triethylamine. The results obtained with the coal-liquids and with several model compounds… more
Date: January 1, 1979
Creator: Li, N. C.; Tewari, K. C. & Hara, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Configurational Diffusion of Coal Macromolecules

Description: As shown in last quarter's report on the configurational diffusion of coal macromolecules, the hindered diffusion data for both TPP and coal macromolecules were significantly different from the theoretical correlations. In order to evaluate the factors which could lead to this difference an error analysis was conducted, and the detailed results reported herein. Generally, we did not find any errors which could account for the deviation from the theory, and thus we conclude that this deviation i… more
Date: January 1, 1990
Creator: Guin, J. A.; Curtis, C. W. & Tarrer, A. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Configurational diffusion of coal macromolecules

Description: The objective of our research was to obtain fundamental information regarding the functional dependence of the diffusion coefficient of coal molecules on the ratio of molecule to pore diameter. That is, the objective of our study was to examine the effect of molecule size and configuration on hindered diffusion of coal macromolecules through as porous medium. To best accomplish this task, we circumvented the complexities of an actual porous catalyst by using a well defined porous matrix with un… more
Date: January 1, 1991
Creator: Guin, J. A.; Curtis, C. W.; Tarrer, A. R.; Kim, S.; Hwang, D.; Chen, C. C. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Modeling of heavy organic deposition

Description: Organic deposition is often a major problem in petroleum production and processing. This problem is manifested by current activities in gas flooding and heavy oil production. The need for understanding the nature of asphaltenes and asphaltics and developing solutions to the deposition problem is well recognized. Prediction technique is crucial to solution development. In the past 5 years, some progress in modeling organic deposition has been made. A state-of-the-art review of methods for modeli… more
Date: January 1, 1992
Creator: Chung, F. T. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Hydrogen bonding in asphaltenes and coal. Quarterly report, January 1--March 31, 1979

Description: In this study, upgraded coal liquids from a blend of 30 weight percent of SRC I with 70 weight percent of SRC II, as well as from SRC II, have been studied by IR and NMR techniques. The variation of structural parameters of the upgraded liquids has been determined as a function of reaction temperature and contact time in the catalytic hydroprocessing. The results indicate that along with the decrease in heteroatom contents, asphaltene content, aromatic content and a corresponding increase in al… more
Date: April 1, 1979
Creator: Li, N. C.; Tewari, K. C. & Hara, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Chemistry and structure of coal-derived asphaltenes, Phase III. Quarterly progress report, July--September 1978

Description: Preparative scale GPC separation of Synthoil asphaltene was carried out on styrene-divinyl benzene packing (Bio-Beads S-X8). The elution took place in the order of high to low molecular weight. Analyses indicate that aromatic ring systems with large saturated substituents elute first followed by more aromatic molecules with less saturated substituents. Infrared measurements on coal-derived asphaltenes were carried out with a large path cell (1 cm) in order to measure absorbance as a function of… more
Date: January 1, 1978
Creator: Yen, T. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Chemistry and structure of coal-derived asphaltenes, Phase III. Quarterly progress report, April--June 1978

Description: Solubility parameters may be calculated for coal liquid derived products by use of a semi-empirical relationship between solubility parameter and refractive index. Thermal treatment of Synthoil coal liquid oil + resin solvent fraction at 235 to 300/sup 0/C resulted in the transformation of oil and resin into asphaltene. Further support of structural characterizations was obtained by use of a combined x-ray and NMR structural characterization procedure which relies on the important x-ray structu… more
Date: January 1, 1978
Creator: Yen, T. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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