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Spin-mapping of coal structures with ESE and ENDOR

Description: The broad goals of this project are to determine by nondestructive magnetic resonance methods chemical and physical structural characteristics of organic parts of native and treated coals. In this project period, we have begun to explore a technique which promises to enable us to follow to course of coal cleaning processes with microscopic spatial resolution. For the past five years, our laboratory has worked on extensions of the EPR technique as applied to coal to address these analytical prob… more
Date: December 1, 1989
Creator: Belford, R. L. & Clarkson, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Spin-mapping of coal structures with ESE and ENDOR

Description: Work reported this quarter (1) continues the study of organic sulfur species in coal with Very High Frequency (VHF) EPR spectroscopy and (2) includes some pulsed EPR work on coals carried out with the S-band ESE spectrometer. A detailed VHF study of one coal from the Illinois Coal Sample Bank is reported, including spectra from separated macerals and solvent extracted coal. Further refinements in the two-species model for interpreting these spectra are presented. It is increasingly apparent tha… more
Date: March 1, 1990
Creator: Belford, R. L. & Clarkson, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Spin-mapping of coal structures with ESE and ENDOR

Description: The broad goals of this project are to determine by nondestructive means -- magnetic resonance techniques -- aspects of chemical and physical structures of organic parts of native and treated coals. We also hope to use related methods to follow the course of certain coal cleaning processes with microscopic spatial resolution. Specific goals include: the nondestructive determination of atomic and molecular structure of sulfur-containing organic species in coal both in its natural state and at va… more
Date: September 1, 1989
Creator: Belford, R. L. & Clarkson, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Spin-mapping of coal structures with ESE and ENDOR. First quarterly report

Description: Nondestructive chemical and physical characterization of whole Illinois coal and separated macerals, both before and after treatment by various desulfurization techniques is being performed using new electron magnetic resonance methods. The chemical structures of sulfur and non-sulfur containing organic species are being measured by the technique of HYPERFINE FINGERPRINT SPECTROSCOPY. Data on hyperfine couplings in a separated vitrinite maceral suggest the presence of small, condensed ring arom… more
Date: December 1, 1988
Creator: Belford, R. L. & Clarkson, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Surface properties of photo-oxidized bituminous coals. Technical progress report, April 1995--June 1995

Description: During this report period, analysis of the vitrinite concentrate samples of the Lower Kittanning (PSOC-1562) and Illinois No. 6 (DECS-24) seams were completed. These results show that the concentrates are in excess of 97 vol. % vitrinite and that the sample remains in good shape for microflotation and GC/MS experiments. Two new coal samples, the hvAb Banner seam (DECS-29) and the mvb Splashdam seam (DECS-30) were collected in mid-June. Preliminary processing of the channel samples suggests that… more
Date: August 1995
Creator: Mitchell, G.; Davis, A. & Chander, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrothermally Treated Coals for Pulverized Coal Injection. Technical Progress Report, April 1995--June 1995

Description: This project is investigating the suitability of hydrothermally dried low-rank coals for pulverized fuel injection into blast furnaces in order to reduce coke consumption. Coal samples from the Beluga coal field and Usibelli Coal Mine, Alaska, are being used for the study. Crushed coal samples were hydrothermally treated at three temperatures, 275, 300 and 325{degrees}C, for residence times ranging from 10 to 120 minutes. Products have been characterized to determine their suitability for pulve… more
Date: July 1995
Creator: Walsh, D. E.; Rao, P. D.; Ogunsola, O. & Lin, H. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Surface properties of photo-oxidized bituminous coals. Technical progress report, January 1995--March 1995

Description: During this report period, vitrinite concentrate samples were prepared from the Illinois No. 6 (DECS-24) and Lower Kittanning (PSOC-1562) seam samples that were collected last year. Some of the analytical information on these concentrates are provided. In addition, preparation of a surface-oxidized powdered vitrinite concentrate of the Pittsburgh seam (DECS-23) sample for microflotation experiments and pyrolysis GC/MS was initiated following development of a procedure for the irradiation sequen… more
Date: May 1995
Creator: Mitchell, G.; Davis, A. & Chander, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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CO{sub 2} SEQUESTRATION POTENTIAL OF TEXAS LOW-RANK COALS

Description: The objectives of this project are to evaluate the feasibility of carbon dioxide (CO{sub 2}) sequestration in Texas low-rank coals and to determine the potential for enhanced coalbed methane (CBM) recovery as an added benefit of sequestration. There were three main objectives for this reporting period, which related to obtaining accurate parameters for reservoir model description and modeling reservoir performance of CO{sub 2} sequestration and enhanced coalbed methane recovery. The first objec… more
Date: February 1, 2005
Creator: McVay, Duane A.; Ayers, Walter B., Jr. & Jensen, Jerry L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of Devonian Black Shales in Kentucky for Potential Carbon Dioxide Sequestration and Enhanced Natural Gas Production Quarterly Report: April-June 2005

Description: Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples wer… more
Date: July 29, 2005
Creator: Nuttall, Brandon C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Advanced Chemistry Basins Project: Final Report

Description: In the next decades, oil exploration by majors and independents will increasingly be in remote, inaccessible areas, or in areas where there has been extensive shallow exploration but deeper exploration potential may remain; areas where the collection of data is expensive, difficult, or even impossible, and where the most efficient use of existing data can drive the economics of the target. The ability to read hydrocarbon chemistry in terms of subsurface migration processes by relating it to the… more
Date: April 5, 2004
Creator: Goddard, William; Meulbroek, Peter; Tang, Yongchun & Cathles, Lawrence, III
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

CO2 Sequestration Potential of Texas Low-Rank Coals Quarterly Report

Description: The objectives of this project are to evaluate the feasibility of carbon dioxide (CO{sub 2}) sequestration in Texas low-rank coals and to determine the potential for enhanced coalbed methane (CBM) recovery as an added benefit of sequestration. The main tasks for this reporting period were to correlate well logs and refine coal property maps, evaluate methane content and gas composition of Wilcox Group coals, and initiate discussions concerning collection of additional, essential data with Anada… more
Date: July 1, 2004
Creator: McVay, Duane A.; Walter B. Ayers, Jr. & Jensen, Jerry L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Surface properties of photo-oxidized bituminous coals. Technical progress report, July--September 1995

Description: During this report period, a new whole-seam channel sample (Ohio {number_sign}4a) was collected and analyzed, together with the Upper Banner and Splash Dam samples obtained last quarter. These additions bring to seven the number of coals obtained for this project and that range in rank from hvCb to mvb. Polished blocks of each coal containing 3-4 mm wide vitrain bands were prepared for contact angle measurements of fresh and photo-oxidized surfaces. An advancing-drop technique was used to measu… more
Date: November 1995
Creator: Mitchell, G.; Polat, H.; Davis, A. & Chander, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Surface properties of photo-oxidized bituminous coals. Technical progress report, December 1993--March 1994

Description: During the report period, channel and block samples of the Pittsburgh seam (DECS-23) were collected from Consolidation Coal Company`s Bailey Mine and were subsequently processed and partly analyzed. Powdered vitrinite concentrates were prepared from the block samples in a nitrogen-filled glovebox, and small coal blocks containing {approximately}5 mm thick vitrain bands were cut from the larger sections. Results of proximate, ultimate and petrographic analyses showed that the concentrate contain… more
Date: April 1994
Creator: Mitchell, G. & Davis, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Hydrothermally treated coals for pulverized coal injection. Final technical report

Description: This project investigated the suitability of hydrothermally dried low-rank coals for pulverized fuel injection into blast furnaces in order to reduce coke consumption. Coal samples from the Beluga coalfield and the Usibelli Coal Mine, Alaska, were used for the study. Crushed coal samples were hydrothermally treated at three temperatures, 275, 300 and 325{degrees}C, for residence times of 10, 60 and 120 minutes. Products were characterized to determine their suitability for pulverized coal injec… more
Date: October 1995
Creator: Walsh, D.E.; Rao, P.D.; Ogunsola, O. & Lin, H.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Surface properties of photo-oxidized bituminous coals. Technical progress report for the period April to June, 1996

Description: During this report period, two vitrinite concentrates were prepared and analyzed from the hvBb Ohio No. 4a and hvAb Lower Kittanning seams. Results show that concentrates of 97 and 96 vol% vitrinite were achieved for the respective samples. Both samples have relatively high concentrations of sulfate sulfur which is the only sign of deterioration. However, in the case of the Lower Kittanning sample the sulfate may have been part of the original sample. Irradiation (photo-oxidation) of all six vi… more
Date: August 1996
Creator: Mitchell, G.; Werner, D.; Davis, A. & Chander, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

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
open access

Spin-mapping of coal structures with ESE and ENDOR

Description: The overall goal of this project is the development of nondestructive techniques for studying the molecular structure of coal by probing the chemical environment of naturally occurring unpaired electrons with a variety of electron magnetic resonance spectroscopies. One exceptionally promising method for investigating molecular structure in complex solids possessing unpaired electrons is Electron Spin Echo Envelope Modulation (ESEEM) spectroscopy. Currently the aim of our S-band ESEEM work is to… more
Date: June 1, 1990
Creator: Belford, R. L. & Clarkson, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Spin-mapping of coal structures with ESE (Electron Spin Echo) and ENDOR (Electron-Nuclear Double Resonance)

Description: Nondestructive chemical and physical characterization of whole Illinois coal and separated macerals, both before and after treatment by various desulfurization techniques is being performed using new electron magnetic resonance methods. The chemical structures of sulfur and non-sulfur containing organic species are being measured by the technique of Hyperfine Fingerprint Spectroscopy. Data on hyperfine couplings in a separated vitrinite maceral suggest the presence of small, condensed ring arom… more
Date: December 1, 1988
Creator: Belford, R. L. & Clarkson, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Spin-mapping of coal structures with ESE and ENDOR (electron nuclear double resonance)

Description: The electron paramagnetic resonance (EPR) and electron nuclear double resonance (ENDOR) spectroscopies that have been used to study coal and coal model systems in our laboratory require spectral simulations in order to extract the available information from the spectra. A procedure has been developed to automate the fitting of spectral parameters in electron paramagnetic resonance (EPR) and related types of spectra. An automated system for simulating such spectra will allow us to obtain better … more
Date: June 1, 1989
Creator: Belford, R. L. & Clarkson, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Spin-mapping of coal structures with ESE and ENDOR (Electron-Nuclear Double Resonance)

Description: Our Laboratory is presently engaged in developing a method to model sulfur-containing compounds in whole coal. It has been established that most of the organic sulfur in coal exists in the form of aromatic groups known as thiophenes. Sulfur-containing aromatic compounds such as thiophene, tetraphenylthiophene and thianthrene were adsorbed onto silica-alumina catalyst surfaces were used as models to emulate coal's anisotropic nature and abundance of unpaired electron spin density. The spectrosco… more
Date: March 1, 1989
Creator: Belford, R. L. & Clarkson, R. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Solid state 13C NMR analysis of shales and coals from Laramide Basins. Final report, March 1, 1995--March 31, 1996

Description: This Western Research Institute (WRI) jointly sponsored research (JSR) project augmented and complemented research conducted by the University of Wyoming Institute For Energy Research for the Gas Research Institute. The project, {open_quotes}A New Innovative Exploitation Strategy for Gas Accumulations Within Pressure Compartments,{close_quotes} was a continuation of a project funded by the GRI Pressure Compartmentalization Program that began in 1990. That project, {open_quotes}Analysis of Press… more
Date: December 31, 1998
Creator: Miknis, F. P.; Jiao, Z. S.; Zhao, Hanqing & Surdam, R. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Chemically modified coal macerals. Separation, density and surface area variations

Description: Two Argonne Premium Coals were O-alkylated and O-acylated using a variety of different reagents, and then separated using density gradient centrifugation (ADGC). The separation data suggested that the hydroxyl groups are fairly evenly distributed in the maceral particles. However, several reagents produced results counter to this generalization, and exhibited enhanced maceral separation. Comparison of ADGC densities and He densities of the modified coals showed several reactivity families that … more
Date: June 1, 1997
Creator: Dyrkacz, G. R. & Bloomquist, C. A. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of an on-line image analysis for assessment of pyrite liberation. Final technical report, 1 September, 1992--31 August, 1993

Description: The degree of pyrite liberation is a key to determine whether a batch of ground coal obtained through a grinding process is acceptable. Currently, the liberation analysis is conducted manually through a microscope with a commercial image analysis software. This procedure is very labor intensive and time consuming. As a result, an automation procedure based on the principles of image processing is proposed to perform the analysis of pyrite/minerals liberation of coal. To make the automated image… more
Date: 1993
Creator: Yen, S. C. M. & Chu, P. T. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Analysis of organic sulfur and nitrogen in coal via tandem degradation methods. [Quarterly] technical report, March 1--May 31, 1993

Description: There is need for alternative methods for determining the nature of organic sulfur and nitrogen compounds in coal. In our research, we apply chemical and thermal degradation techniques to render coal amenable to standard gas chromatography characterization. Standard density gradient centrifugation successfully isolated vitrinite from the IBC101 coal, whereas the multi-step high resolution method was required to isolate liptinite and inertinite macerals, which are minority constituents. Analytic… more
Date: September 1, 1993
Creator: Kruge, Michael A. & Palmer, Stephen R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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