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Vapor pressures and heats of vaporization of primary coal tars. Quarterly technical progress report, 1 October--31 December 1994

Description: The vapor pressure correlations that exist at present for coal tars are very crude and they are not considered reliable to even an order of magnitude when applied to tars. The present project seeks to address this important gap in the near term by direct measurement of vapor pressures of coal tar fractions, by application of well-established techniques and modifications thereof. The principal objectives of the program are to: (1) obtain data on the vapor pressures and heats of vaporization of t… more
Date: April 1, 1995
Creator: Suuberg, E.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Determination of the Forms of Nitrogen Released in Coal Tar During Rapid Devolatilization. Semi-Annual Report, November 1, 1995--April 30, 1996

Description: Control of emissions of nitrogen oxides (NO{sub x}) from coal combustion systems is becoming a major design and retrofit consideration. Most NO{sub x} in coal combustion systems comes from nitrogen in the fuel, rather than from nitrogen in the air. Practical emission control strategies include burner design strategies (e.g., low NO{sub x} burners), overfire air, reburning, selective non-catalytic reduction (SNCR) using reduction agents such as NH{sub 3} or urea, and selective catalytic reductio… more
Date: April 30, 1996
Creator: Fletcher, T. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Vapor pressures and heats of vaporization of primary coal tars. Quarterly technical progress report, July 1--September 30, 1995

Description: There is significant current interest in general area of coal pyrolysis, particularly because of the central role of pyrolysis in all thermally driven coal conversion processes-gasification, combustion, liquefaction, mild gasification, or thermal beneficiation. There remain several key data needs in these application areas. Among them is a need for more reliable correlation for prediction of vapor pressure of heavy, primary coal tars. The vapor pressure correlations that exist at present for co… more
Date: December 31, 1995
Creator: Suuberg, E.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Molecular accessibility in solvent swelled coal. Quarterly report, November 1991

Description: The EPR-spin probe method was used to study the swelling of covalently cross-linked 2%, 4%, 6%, 8% and 12% polystyrene-divinyl benzene copolymers, used as models of APCS coal structural elements. The results were compared with swelling studies on APCS coals and confirmed results showing that coal was polymeric, that it had covalent cross-links increasing with rank, that it was structurally anisotropic, and that its swelling was anisotropic. The low temperature swelling of Argonne Premium Coal S… more
Date: December 31, 1991
Creator: Kispert, L. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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[Advanced Coal Conversion Process]. Technical progress report, July 1, 1992--September 30, 1992

Description: This report contains a description of the technical progress made on the Advanced Coal Conversion Process (ACCP) Demonstration Project from July 1, 1992, through September 30, 1992. The ACCP Demonstration Project is a US Department of Energy (DOE) Clean Coal Technology Project. The Cooperative Agreement defining this project is between DOE and the Rosebud SynCoal Partnership. This project demonstrates an advanced, thermal, coal-drying process, coupled with physical cleaning techniques, that is … more
Date: December 1, 1993
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermodynamic properties of pulverized coal during rapid heating devolatilization processes. Quarterly progress report, July--September 1992

Description: Knowledge of the thermodynamic and morphological properties of coal associated with rapid heating decomposition pathways is essential to progress in coal utilization technology. Specifically, knowledge of the heat of devolatilization, surface area and density of coal as a function of rank characteristics, temperature and extent of devolatilization in the context of rapid heating conditions is required both, for the fundamental determination of kinetic parameters of coal devolatilization, and to… more
Date: November 1, 1992
Creator: Proscia, W. M. & Freihaut, J. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pyrolysis and gasification of coal at high temperatures. Quarterly progress report No. 5, September 15, 1988--December 15, 1988

Description: Coals of different ranks will be pyrolyzed in a microscope hot-stage reactor using inert and reacting atmospheres. The macropore structure of the produced chars will be characterized using video microscopy and digital image processing techniques to obtain pore size distributions. Comparative studies will quantify the effect of pyrolysis conditions (heating rates, final heat treatment temperatures, particle size and inert or reacting atmosphere) on the pore structure of the devolatilized chars. … more
Date: December 31, 1988
Creator: Zygourakis, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pyrolysis and gasification of coal at high temperatures. Annual progress report No. 1, September 15, 1987--September 15, 1988

Description: Particles from two parent coals (Illinois {number_sign}6 and lignite) were pyrolyzed in a nitrogen atmosphere using a captive sample microreactor capable of achieving heating rates as high as 1000{degrees}C/s. Direct measurements on digitized image of char particle cross-sections and a stereological model were used to characterize the macropore structure of chars. Macroporosites, pore size distributions and surface areas were accurately measured allowing us to quantify the effects of pyrolysis … more
Date: December 31, 1988
Creator: Zygourakis, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The use of solid-state NMR techniques for the analysis of water in coal and the effect of different coal drying techniques on the structure and reactivity of coal. Quarterly report, June 1--August 31, 1993

Description: One area for improvement in the economics of coal liquefaction is coal drying, particularly for the lower rank coals. However, there is considerable evidence to show that drying has a detrimental effect on the liquefaction behavior of coals. Regarding the liquefaction of coal, there does not appear to have been any systematic study of the methods of coal drying on coal structure and the role water plays in enhancing or lessening coal reactivity toward liquefaction. To conduct this study two coa… more
Date: November 1, 1993
Creator: Netzel, D. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Structure and thermochemical kinetic studies of coal pyrolysis. Final technical report

Description: The structure and kinetics of low rank coals, namely, Montana Rosebud subbituminous and Beulah lignite coals have been studied. C0{sub 2} laser heating of separated arrays of particles at high flux levels has made possible the investigation of the pyrolysis and char oxidation processes of lignite and subbituminous coal particles as a function of exposure time at laser fluxes of 200--300 w/cm{sup 2}. The Beulah lignite and Rosebud subbituminous coals studied were supplied by the Penn State Coal … more
Date: December 31, 1994
Creator: Dodoo, J.N.D. & Hetzberg, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Molecular accessibility in oxidized and dried coals. Quarterly report

Description: The objective of this research project is to determine the molecular and structural changes that occur in swelled coal as a result of oxidation and moisture loss both in the presence and absence of light using the EPR spin pore method. The proposed study will make it possible to deduce the molecular accessibility distribution in swelled, oxidized APCS coal as a function of sunlight for each rank as a function of (1) size (up to 6 nm) and shape, (2) the relative acidic/basic reactive site distri… more
Date: September 1, 1996
Creator: Kispert, L. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Magnetic relaxation--coal swelling, extraction, pore size. Technical progress report, October 1, 1991--December 31, 1991

Description: The grant activities during this period fall into four categories: (1) Completion of preparatory work, (2) Procedure refinement and actual preparation of whole coal, coal residue, coal extract and swelled coal samples for NMR studies, (3) Related studies of coal photolysis that employ materials from preliminary extractions and that examine the u.v.-visible and mass spectra of the extracts and (4) Continued investigations of the pulsed EPR characteristics of the whole coal samples that were prep… more
Date: December 31, 1991
Creator: Doetschman, D. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization and supply of coal based fuels. Quarterly technical progress report, February 1, 1987--April 30, 1987

Description: Contract objectives are as follows: develop fuel specifications to serve combustor requirements; select coals having appropriate compositional and quality characteristics as well as an economically attractive reserve base; provide quality assurance for both the parent coals and the fuel forms; and deliver premium coal-based fuels to combustor developers as needed for their contract work. During the second quarter of this contract effort, the primary activities were involved with: continuation o… more
Date: July 1, 1987
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Coal precursors for carbon molecular sieves (CMS): Appendices A through L. Final report, October 1, 1994--March 31, 1996

Description: The data for each coal sample used in this study are included in a separate appendix. The information for each coal is presented in the following order: coal sample data (literature); coal sample data (measured); thermogravimetric data; mass spectroscopy data; mercury intrusion pore analysis; quantachrome gas sorption analysis (BET) using nitrogen (raw whole coal sample); quantachrome gas sorption analysis (BET) using nitrogen (activated whole coal sample; and plot of FTIR (DRIS) information ab… more
Date: March 31, 1996
Creator: Kopp, O. C.; Sparks, C. R.; McKinney, M. L.; Fuller, Jr., E. L. & Rogers, M. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermolysis of phenethyl phenyl ether: A model of ether linkages in low rank coal

Description: Currently, an area of interest and frustration for coal chemists has been the direct liquefaction of low rank coal. Although low rank coals are more reactive than bituminous coals, they are more difficult to liquefy and offer lower liquefaction yields under conditions optimized for bituminous coals. Solomon, Serio, and co-workers have shown that: in the pyrolysis and liquefaction of low rank coals, a low temperature cross-linking reaction associated with oxygen functional groups occurs before t… more
Date: September 1, 1994
Creator: Britt, P. F.; Buchanan, A. C., III & Malcolm, E. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Methane formation and retention in coal. Quarterly technical progress report, July 1, 1991--September 30, 1991

Description: The methane content of coal seams in Utah and Colorado are measured in situ as well as in the laboratory and correlated with the geological and geochemical history of the seams and surrounding strata. Chemical and physical properties are measured in the laboratory for coals that contain methane and coals of similar rank which do not contain methane. Methane yields on pyrolysis are used to measure the propensity of coals to form additional methane. Methane formation and retention will be interpr… more
Date: December 31, 1991
Creator: Hucka, V. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The single electron chemistry of coals. [Quarterly] report, January 1, 1991--March 31, 1991

Description: The simplest explanation for these shifts in the infrared spectra is there exists in coal single electron donors which are capable of transferring an electron to TCNQ in the ground state. All of the TCNQ placed in the coal appears to be converted to the radical anion as displayed in the IR spectrum for all of the coals except for the 100% loading.
Date: April 22, 1991
Creator: Larsen, John W. & Flowers, Robert A., II
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Coal combustion: Effect of process conditions on char reactivity. Quarterly technical report, September 1, 1991--December 1, 1991

Description: The project will quantify the effect of the following pyrolysis conditions on the macropore structure and on the subsequent reactivity of chars: (a) pyrolysis heating rate; (b) final heat treatment temperature (HTT); (c) duration of heat treatment at HTT (or soak time); (d) pyrolysis atmosphere (N{sub 2} or O{sub 2}/N{sub 2} mixtures); (e) coal particle size (100 {endash} 1000 {mu}m in diameter); (f) sulfur-capturing additives (limestone); and (g) coal rank. Pyrolysis experiments will be carrie… more
Date: December 31, 1991
Creator: Zygourakis, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of surface chemistry on the porous structure of coal. Quarterly technical progress report, January 1996--March 1996

Description: The primary objective of this work is to use {sup 129}Xe NMR to characterize the microporous structure of coals. Another objective is to use this technique to describe the effect of controlled opening of the micropores in a microporous carbon by oxygen chemisorption/desorption. The primary goal of the NMR work is to measure the micropore sizes in coal; more broadly, it is to better tailor the {sup 129}Xe NMR method for use with coal, and to investigate other ways it may be used to describe pore… more
Date: August 1, 1996
Creator: Anderson, Stasia A.; Radovic, Ljubisa R. & Hatcher, Patrick G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fundamental study of ash formation and deposition: Effect of reducing stoichiometry. Final report, April 1, 1993--June 30, 1995

Description: The technical objectives of this project are: (1) To identify the partitioning of inorganic coal constituents among vapor, submicron fume, and fly ash products generated during the combustion of pulverized coal under a variety of combustion conditions. Fuel lean and fuel rich combustion conditions are considered. (2) To identify and quantify the fundamental processes by which the transformations of minerals and organically-associated inorganic species occur. Emphasis is placed on identifying an… more
Date: September 1, 1995
Creator: Bool III, L. E.; Helble, J. J. & Shah, N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of organic sulfur and nitrogen in coal via tandem degradation methods. Technical report, 1 December 1992--28 February 1993

Description: N/C and S/C ratios show only minor differences between asphaltenes and coal on this basis, the asphaltenes continue to appear to be good surrogates for the characterization of organic acid rain precursors in coal. Alkylmethoxythiophene carboxylic acids (ATCA) are detected in all dichromate oxidation products analyzed to date. Relative concentrations of ATCA compounds are directly proportional to the sample`s bulk organic sulfur contents. Concentrations of ATCA compounds in oxidation products de… more
Date: May 1, 1993
Creator: Kruge, M. A.; Palmer, S. R. & Ho, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Sequential low-temperature depolymerization and liquefaction of US coal. Final report, January 1, 1987--January 1, 1991

Description: Based on the above described differences in the reactivity of intercluster linkages, an effective new procedure for low-temperature coal depolymerization-liquefaction was proposed and initially examined in our laboratory and then further developed in the framework of this project. The pre-extraction with THF removes most of the easily extractable material within the coal network, leaving the porous system of the coal more susceptible to catalyst impregnation. During subsequent impregnation, the… more
Date: May 1, 1992
Creator: Shabtai, J. S. & Wiser, W. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization and supply of coal based fuels. Quarterly report, May 1, 1987--July 31, 1987

Description: Contract objectives are as follows: Develop fuel specifications to serve combustor requirements. Select coals having appropriate compositional and quality characteristics as well as an economically attractive reserve base. Provide quality assurance for both the parent coals and the fuel forms. Deliver premium coal-based fuels to combustor developers as needed for their contract work. During the third quarter of this contract (May 1 through July 31, 1987) the primary activities were involved wit… more
Date: September 1, 1987
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Pyrolysis and gasification of coal at high temperatures. Quarterly progress report No. 7, March 15, 1988--June 15, 1989

Description: Coals of different ranks will be pyrolyzed in a microscope hot-stage reactor using inert and reacting atmospheres. The macropore structure of the produced chars will be characterized using video microscopy and digital image processing techniques to obtain pore size distributions. Comparative studies will quantify the effect of pyrolysis conditions (heating rates, final heat treatment temperatures, particle size and inert or reacting atmosphere) on the pre structure of the devolatilized chars. T… more
Date: December 31, 1989
Creator: Zygourakis, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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