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Low severity coal liquefaction promoted by cyclic olefins. Quarterly report, April--June 1992

Description: Low severity coal liquefaction allows for solubilization of coal with reduced gas make. These lower severity conditions may result in some selective bond rupture. Promotion of coal solubilization through hydrogen transfer using highly active and effective hydrogen donors is the objective of this study. The highly effective donors being tested are cyclic olefins. Representative cyclic olefins are isotetralin, which is 1,4,5,8-tetrahydronaphthalene, and 1,4,5,8,9,10-hexahydroanthracene. These compounds are hydroaromatics without aromatic rings and have been shown to be highly effective donors. The objective of the work performed in this study during this quarter was to evaluate reaction parameters for low severity liquefaction reactions using the cyclic olefin, hexahydroanthracene, and the aromatic, anthracene. These model compounds were reacted under a variety of conditions to evaluate their reactivity without coal. The reactions were performed under both thermal and catalytic conditions. Finely divided catalysts from different molybdenum precursors were used to determine their activity in promoting hydrogenation and hydrogen transfer at low severity conditions. The catalysts used were Molyvan L, sulfurized oxymolybdenum dithiocarbamate, molybdenum naphthenate, and Molyvan 822, organo molybdenum dithiocarbamate.
Date: July 27, 1992
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

Restricted mass transport effects on free radical reactions

Description: Coal possesses a complex chemical and physical structure. The cross-linked, network structure can lead to alterations in normal thermally-induced, free-radical decay pathways as a consequence of restrictions on mass transport. Moreover, in coal liquefaction, access of an external hydrogen donor to a reactive radical site can be hindered by the substantial domains of microporosity present in coals. However, previous work indicates that diffusion effects do not appear to be playing an important role in this coal conversion chemistry. Several possible explanations for this phenomenon were advanced including the potential involvement of a hydrogen hopping/radical relay mechanism recently discovered model systems in the authors laboratories. The authors have employed silica-anchored compounds to explore the effects of restricted mass transport on the pyrolysis mechanisms of coal model compounds. In studies of two-component systems, cases have been discovered where radical centers can be rapidly relocated in the diffusionally constrained environment as a consequence of rapid serial hydrogen atom transfers. This chemistry can have substantial effects on thermal decomposition rates and on product selectivities. In this study, the authors examine additional surfaces to systematically investigate the impact of molecular structure on the hydrogen atom transfer promoted radical relay mechanism. Silica-attached 1,3-diphenylpropane ({approx}Ph(CH{sub 2}){sub 3}Ph, or {approx}DPP) was chosen as the thermally reactive component, since it can be considered prototypical of linkages in coal that do not contain weak bonds easily cleaved at coal liquefaction temperatures (ca. 4000 {degrees}C), but which crack at reasonable rates if benzylic radicals can be generated by hydrogen abstraction. The rate of such hydrogen transfers under restricted diffusion will be highly dependent on the structure and proximity of neighboring molecules.
Date: September 1, 1994
Creator: Buchanan, A. C. III; Britt, P. F. & Thomas, K. B.
Partner: UNT Libraries Government Documents Department

High conversion of coal to transportationn fuels for the future with low HC gas production. Progress report No. 7, April 1--June 30, 1994

Description: The objective is to produce a Synthetic crude from coal at a cost lower than $30.00 per barrel (Task A). A second objective is to produce a fuel which is low in aromatics, yet of sufficiently high octane number for use in the gasoline-burning transportation vehicles of today. To meet this second objective, research was proposed, and funding awarded, for conversion of the highly-aromatic liquid product from coal conversion to a product high in isoparaffins, which compounds in the gasoline range exhibit a high octane number (Task B). Experimental coal liquefaction studies conducted in a batch microreactor in our laboratory have demonstrated potential for high conversions of coal to liquids with low yields of hydrocarbon (HC) gases, hence small consumption of hydrogen in the primary liquefaction step. Ratios of liquids/HC gases as high as 30/1, at liquid yields as high as 82% of the coal by weight, have been achieved. The principal objective of this work is to examine how nearly we may approach these results in a continuous-flow reactor system, at a size sufficient to evaluate the process concept for production of transportation fuels from coal. Accomplishments for this period are described.
Date: July 1, 1994
Creator: Wiser, W. H. & Oblad, A. G.
Partner: UNT Libraries Government Documents Department

Low severity coal liquefaction promoted by cyclic olefins. Quarterly report, January--March 1993

Description: The combination of some of these methods could further improve low severity conversion. It seems logical that a combination of a proven pretreatment technique with a good dissolution catalyst or a good hydrogen donor would increase reactivity. The importance of surface chemistry with yield and nature of reactions shown in early research indicates the physical importance of pretreatment. Swelling of the coal with an organic solvent improves the contact. This good contact is also important to slowing retrogressive reactions. The best conversions come when the initial products of liquefaction are preserved. In addition to the physical importance of pretreatment, there is a chemical advantage. Shams saw not only the effect of minimization of organic oxygen coupling reactions, but with his process there also seemed to be a demineralization. The minerals removed the catalysts for retrogressive reactions. The chemistry of liquefaction is still not well understood. Stansberry`s attempt to determine whether catalysts liberate species or just further decomposition was largely inconclusive. There was improvement in conversion so the catalysts seemingly assisted in bond breakage. These good catalytic effects were also seen in the work involving coprocessing. The most compelling factor in each of these procedures, is the ability of the coal to receive the hydrogen that it needs to be liquefied. Bedell and Curtis (1991) found that cyclic olefins gave their hydrogen up much more readily than did hydroaromatics. The coal conversion was a significantly improved. The combination of retrogressive reaction suppression and good hydrogen donability should provide for good coal conversion. It was this reasoning that influenced the decision to investigate a combination of the HCl/methanol pretreatment and the usage of cyclic olefins as hydrogen donors. The increased reactivity of the pretreated coal should enhance the effect of the hydrogen donability of the cyclic olefins.
Date: July 1, 1993
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

The role of the resid solvent in co-processing with finely divided catalysts. Quarterly report, January--March 1993

Description: The overall objective of this project is to evaluate the role of the resid in coprocessing. The primary purpose of this initial work was to establish under thermal and catalytic reaction conditions whether hydrogen transfer occurred between cycloalkane type structures that are present in resids and aromatics that are present in coal and liquefied coal. The research this quarter focused upon evaluating different reaction systems for performing model donor and model acceptor studies. The first system that was evaluated involved anthracene (ANT) as the model acceptor. Previous results had shown that ANT did not convert substantially in a thermal reaction at 380{degrees}C (Wang 1992); however, more was converted (about 50%) at 440{degrees}C. The results from the reactions performed last quarter indicated that substantial hydrogenation of ANT occurred thermally at 440{degrees}C; more than had been observed previously. The reactors that were used, though, had contained substantial amounts of catalysts prior to the performance of the thermal reactions. Hence, the passivity of the reactors was questioned and new reactors were fabricated. Some of the reactions using ANT were performed again and are reported herein. The second part of the work performed this quarter was to evaluate hydrogen transfer from the cycloalkane, perhydropyrene (PHP), to the aromatic phenanthrene (PHEN). Reactions were performed at a 1:1 PHP to PHEN weight ratio and with a 5:1 PHP to PHEN ratio. The reactions were performed thermally and catalytically at 400 and 425{degrees}C using molybdenum naphthenate and nickel octoate as catalysts. Reactions were also performed with added sulfur either as elemental sulfur or benzothiophene.
Date: August 1, 1993
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

Studies of transition states and radicals by negative ion photodetachment

Description: Negative ion photodetachment is a versatile tool for the production and study of transient neutral species such as reaction intermediates and free radicals. Photodetachment of the stable XHY{sup {minus}} anion provides a direct spectroscopic probe of the transition state region of the potential energy surface for the neutral hydrogen transfer reaction X + HY {yields} XH + Y, where X and Y are halogen atoms. The technique is especially sensitive to resonances, which occur at a specific energy, but the spectra also show features due to direct scattering. We have used collinear adiabatic simulations of the photoelectron spectra to evaluate trail potential energy surfaces for the biomolecular reactions and have extended the adiabatic approach to three dimensions and used it to evaluate empirical potential energy surfaces for the I + Hl and Br + HI reactions. In addition, we have derived an empirical, collinear potential energy surface for the Br + HBr reaction that reproduces our experimental results and have extended this surface to three dimensions. Photodetachment of a negative ion can be also used to study neutral free radicals. We have studied the vibrational and electronic spectroscopy of CH{sub 2}NO{sub 2} by photoelectron spectroscopy of CH{sub 2}NO{sub 2}{sup {minus}}, determining the electron affinity of CH{sub 2}NO{sub 2}, gaining insight on the bonding of the {sup 2}B{sub 1} ground state and observing the {sup 2}A{sub 2} excited state for the first time. Negative ion photodetachment also provides a novel and versatile source of mass-selected, jet-cooled free radicals. We have studied the photodissociation of CH{sub 2}NO{sub 2} at 270, 235, and 208 nm, obtaining information on the dissociation products by measuring the kinetic energy release in the photodissociation.
Date: December 1, 1991
Creator: Metz, R. B.
Partner: UNT Libraries Government Documents Department

Investigation of the use of a recycle stream to mediate hydrogen transfer to improve the conversion of eastern oil shale to liquid products

Description: The processing of eastern oil shale has long been known to require the addition of hydrogen to increase the oil yield. Several researchers, have investigated the use of both high pressure hydrogen and hydrogen donor solvents. Much of the donor solvent work has used pure,compounds such as tetralin and has not addressed the use of-a more realistic solvent such as one derived from the production process itself. The work reported herein is for the research Task 1.2.2, Process Studies, in the Annual Project Plan, October l, 1990--September 30, 1991, of the Cooperative Agreement. In the study, a shale oil-derived, recycle oil was used to mediate the transfer of hydrogen to eastern oil shale. The work was divided into two main parts which correspond to the two main portions of the Hydrogen-Extraction (H-E{trademark}) process: (1) the shale oil extraction which involves the use of a donor solvent to aid in the extraction of the shale oil and (2) the regeneration of the donor solvent to a hydrogen-rich state ready for recycle. The results of the investigation to evaluate shale oil extraction using a shale oil-derived donor solvent suggest that temperature had the, greatest effort on organic conversion. At a temperature of 425{degrees}C (197{degrees}F), a yield of 130% of Fischer assay was obtained using tetralin as a donor solvent. At the same temperature, only 110% of Fischer assay could be obtained using a middle distillate as a donor solvent.
Date: June 1, 1944
Creator: Barbour, F. A.; Guffey, F. D.; Thomas, K. P. & Blake, R. F.
Partner: UNT Libraries Government Documents Department

Magnetic resonance studies of photo-induced electron transfer reactions. Final report, June 1, 1990--May 31, 1993

Description: Fourier Transform Electron Paramagnetic Resonance (FT EPR) is useful in study of photochemical reactions: a microwave pulse rotates the electron spin magnetization vector from z (magnetic field) into xy plane ({pi}/2 pulse); the time evolution of magnetization in xy plane, the free induction decay (FID), is sampled. Fourier transform of FID gives the frequency domain EPR spectrum of the free radicals, and the method is ideal for time-resolved studies of free radicals produced by pulsed-laser excitation. Investigations of electron transfer reactions focused on porphyrin (donor) - quinone (acceptor) systems. First, two hydrogen abstraction reactions were studied with FT EPR: photoreduction of acetone with 2-propanol, yielding the acetone ketyl radical, and the reaction of 2-propanol with t-butoxy radicals. Then, the FT EPR study of benzoquinone or duroquinone anion radicals generated by pulsed-laser induced electron transfer from zinc tetraphenylporphyrin (ZnTPP) or tetrasulfonated Zn(TPP), was carried out in homogeneous solution, micellar solutions, and silica gel. Finally, FT EPR was used to study electron transfer quenching of triplet C{sub 60} by electron donors.
Date: November 1, 1992
Creator: van Willigen, H.
Partner: UNT Libraries Government Documents Department

Improved performance in coprocessing through fundamental and mechanistic studies in hydrogen transfer and catalysis. Quarterly report, September 26, 1989--December 26, 1989

Description: To gain a fundamental understanding of the role and importance of hydrogen transfer reactions in thermal and catalytic coprocessing by examining possible hydrogen donation from cycloalkane/aromatic systems and by understanding the chemistry and enhanced reactivity of hydrotreated residuum, as well as by enriching petroleum solvent with potent new donors, nonaromatic hydroaromatics, thereby promoting hydrogen transfer reactions in coprocessing. The detailed results of experiments performed on several subtasks during the quarter are presented.
Date: December 31, 1989
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

Improved performance in coprocessing through fundamental and mechanistic studies in hydrogen transfer and catalysis. Final report, September 26, 1989--March 31, 1993

Description: The key results obtained from this research project are given: (1) Hydrogen transfer from naphthenes to aromatics, coal and resid occurred at coprocessing temperatures and in a N{sub 2} atmosphere; (2) Hydrogen donors ranked in reactivity as cyclic olefins (nonaromatic hydroaromatic compounds) > hydroaromatic compounds > naphthenes. This ranking held regardless of the type of atmosphere, hydrogen or nitrogen, used; (3) Resids reduced by the Birch method transferred substantially more hydrogen to the aromatic acceptor than did the parent resids under coprocessing conditions; (4) Hydropretreatment of resids resulted in enhanced coal conversion compared to the parent resid; (5) Addition of hydrogen donors such as cyclic olefins or hydroaromatic donors increased the amount of coal conversion during coprocessing. Cyclic olefins and the active hydroaromatic donor, dihydroanthracene, showed the highest level of hydrogen donability. Tetralin and octahydroanthracene showed low reactivity; (6) Reduced resids were more effective in coprocessing than the parent resids, in terms of enhanced coal conversion; (7) Thermal and catalytic reactivity of cyclic olefins under nitrogen and hydrogen atmospheres was much higher than conventional hydroaromatic donors when no aromatic acceptor was present; (8) Reactivity of hydrogen donors was dependent upon the reactivity of the acceptor as well as that of the donors; (9) Three-ring hydrogen donors, dihydroanthracene and hexahydroanthracene, were most effective for transferring hydrogen to the Argonne coals while octahydroanthracene was the least reactive; (10) The kinetics data obtained for thermal and catalytic reactions involving cyclic olefins and hydroaromatic donors were adequately modeled by pseudo-first order kinetics; and (11) {Delta}G values calculated for cyclic olefins and hydroaromatic donors based on kinetics data adequately represented the reactivity observed experimentally.
Date: December 31, 1993
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

Diosmacycloalkanes as models for the formation of hydrocarbons from surface methylenes. Progress report, November 1, 1991--October 31, 1992

Description: We are making progress on our investigation of the mechanism of olefin exchange with Os{sub 2}(C{sub 2}H{sub 4})(CO){sub 8}. We are probing this system by kinetic study of the reaction of Os{sub 2}(C{sub 2}H{sub 4})(CO){sub 8} with butyl acrylate (BA) under various pressures of ethylene.
Date: May 1, 1992
Creator: Norton, J. R.
Partner: UNT Libraries Government Documents Department

Improved performance in coprocessing through fundamental and mechanistic studies in hydrogen transfer and catalysis. Quarterly report, December 27, 1990--March 26, 1991

Description: The objective is to gain a fundamental understanding of the role and importance of hydrogen transfer reactions in thermal and catalytic coprocessing by examining possible hydrogen donation from cycloalkane/aromatic systems and by understanding the chemistry and enhanced reactivity of hydrotreated residuum, as well as by enriching petroleum solvent with potent new donors, nonaromatic hydroaromatics, thereby promoting hydrogen transfer reactions in coprocessing. The detailed results of experiments performed on several subtasks during the quarter are presented.
Date: December 31, 1991
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

Coprocessing through fundamental and mechanistic studies in hydrogen transfer and catalysis. Quarterly report, March 28, 1992--June 30, 1992

Description: Hydrogen transfer from naphthenes to aromatics, coal, resid, and coal plus resid has been investigated at 430{degree}C in a N{sub 2} atmosphere. The reaction of perhydropyrene (PHP) with anthracene (ANT) resulted in the formation of pyrene (PYR) and dihydroanthracene. The weight percents of the products formed varied according to the initial ratio of ANT/PHP with a minimum appearing at a 2:1 weight ratio. Increased reaction times and high ANT/PHP ratios also yielded tetrahydroanthracene (THA). Reactions of Illinois No. 6 coal from the Argonne Premium Coal Sample Bank with PHP, ANT, and PYR resulted in higher coal conversion with PHP and lower with ANT and PYR. Reactions of PHP with resid resulted in less retrogressive reactions occurring in the resid than with either PYR or ANT. Apparent hydrogen transfer from coal or resid to ANT and PYR was observed. Combining PHP with ANT or PYR with coal, resid or coal plus resid yielded higher conversions and less retrogressive reactions. Hydrogen transfer occurred from PHP to ANT or PYR and to the coal and resid as evinced by the increased conversion.
Date: December 31, 1992
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

Improved performance in coprocessing through fundamental and mechanistic studies in hydrogen transfer and catalysis. Quarterly report, September 27, 1990--December 26, 1990

Description: The objective is to gain a fundamental understanding of the role and importance of hydrogen transfer reactions in thermal and catalytic coprocessing by examining possible hydrogen donation from cycloalkane/aromatic systems and by understanding the chemistry and enhanced reactivity of hydrotreated residuum, as well as by enriching petroleum solvent with potent new donors, nonaromatic hydroaromatics, thereby promoting hydrogen transfer reactions in coprocessing. The detailed results of experiments performed on several subtasks during the quarter are presented.
Date: December 31, 1990
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

Coprocessing through fundamental and mechanistic studies in hydrogen transfer and catalysis. Quarterly report, December 27, 1991--March 27, 1992

Description: The research conducted this quarter evaluated hydrogen transfer from resids reduced using the Birch reduction method and their corresponding parent resid to an aromatic acceptor, anthracene (ANT). The reactions involved thermal and catalytic reactions using sulfur introduced as thiophenol. This catalyst has been shown by Rudnick to affect the hydrogen transfer from cycloalkane to aromatics/or coal. The purpose of this current study was to evaluate the efficacy of hydrogen transfer from the hydrogen-enriched reduced resid to an aromatic species and to compare that to the hydrogen transfer from the original resid. The analyses performed to evaluate hydrogen transfer were the determination of product slates from the hydrogenation of ANT and the fractionation of the resid into solubility fractions after reaction with ANT. The amount of coal conversion to THF solubles was higher in the coprocessing reactions with the reduced resids compared to the reactions with the corresponding untreated resid. The reduction of the resids by the Birch method increased the hydrogen donating ability of the resid to the same level as that obtained with the introduction of isotetralin (ISO) to the original resid. The ISO was introduced at a level of 0.5 wt % donable hydrogen. Both the original resids and the resids reduced by the Birch method were reacted in the presence of an aromatic species, anthracene (ANT). These reactions were performed under both nitrogen and hydrogen atmospheres at a pressure of 1250 psig introduced at ambient temperature. The reactions were performed both thermally and catalytically at 380{degree}C for 30 minutes. The catalyst used was thiophenol which is the same catalyst as has been used in the previously reported model compound studies involving hydrogen transfer from cycloalkanes to aromatics.
Date: December 31, 1992
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

Improved performance in coprocessing through fundamental and mechanistic studies in hydrogen transfer and catalysis. Quarterly report, June 27, 1991--September 26, 1991

Description: The objective is to gain a fundamental understanding of the role and importance of hydrogen transfer reactions in thermal and catalytic coprocessing by examining possible hydrogen donation from cycloalkane/aromatic systems and by understanding the chemistry and enhanced reactivity of hydrotreated residuum, as well as by enriching petroleum solvent with potent new donors, nonaromatic hydroaromatics, thereby promoting hydrogen transfer reactions in coprocessing. The detailed results of experiments performed on several subtasks during the quarter are presented.
Date: December 31, 1991
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

Improved performance in coprocessing through fundamental and mechanistic studies in hydrogen transfer and catalysis. Quarterly report, March 27, 1991--June 26, 1991

Description: The objective is to gain a fundamental understanding of the role and importance of hydrogen transfer reactions in thermal and catalytic coprocessing by examining possible hydrogen donation from cycloalkane/aromatic systems and by understanding the chemistry and enhanced reactivity of hydrotreated residuum, as well as by enriching petroleum solvent with potent new donors, nonaromatic hydroaromatics, thereby promoting hydrogen transfer reactions in coprocessing. The detailed results of experiments performed on several subtasks during the quarter are presented.
Date: December 31, 1991
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

Improved performance in coprocessing through fundamental and mechanistic studies in hydrogen transfer and catalysis. Quarterly report, December 26, 1989--March 26, 1990

Description: To gain a fundamental understanding of the role and importance of hydrogen transfer reactions in thermal and catalytic coprocessing by examining possible hydrogen donation from cycloalkane/aromatic systems and by understanding the chemistry and enhanced reactivity of hydrotreated residuum, as well as by enriching petroleum solvent with potent new donors, nonaromatic hydroaromatics, thereby promoting hydrogen transfer reactions in coprocessing. The detailed results of experiments performed on several subtasks during the quarter are presented.
Date: December 31, 1990
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

The role of the resid solvent in co-processing with finely divided catalysts. Quarterly report, July--September 1992

Description: Primary purpose is to establish under thermal and catalytic reaction conditions whether hydrogen transfer occurred between cycloalkane type structures present in resids and aromatics present in coal and liquefied coal. Idea was to determine if hydrogen could be transferred from the cycloalkane to the atomatic in a hydrogen atmosphere, which is always present in co-processing. This document gives an extensive literature review, as well as a brief account of the experimental work. 3 tabs, 26 refs.
Date: March 23, 1993
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

Fundamental reaction pathways during coprocessing

Description: The objective of this research was to investigate the fundamental reaction pathways in coal petroleum residuum coprocessing. Once the reaction pathways are defined, further efforts can be directed at improving those aspects of the chemistry of coprocessing that are responsible for the desired results such as high oil yields, low dihydrogen consumption, and mild reaction conditions. We decided to carry out this investigation by looking at four basic aspects of coprocessing: (1) the effect of fossil fuel materials on promoting reactions essential to coprocessing such as hydrogen atom transfer, carbon-carbon bond scission, and hydrodemethylation; (2) the effect of varied mild conditions on the coprocessing reactions; (3) determination of dihydrogen uptake and utilization under severe conditions as a function of the coal or petroleum residuum employed; and (4) the effect of varied dihydrogen pressure, temperature, and residence time on the uptake and utilization of dihydrogen and on the distribution of the coprocessed products. Accomplishments are described.
Date: December 1, 1992
Creator: Stock, L. M. & Gatsis, J. G.
Partner: UNT Libraries Government Documents Department

Coprocessing through fundamental and mechanistic studies in hydrogen transfer and catalysis. Quarterly report, September 26, 1991--December 26, 1991

Description: The research conducted during this quarter evaluated hydrogen transfer from hydroaromatics and cyclic olefins to aromatics under thermal and catalytic conditions. The reactions under study involved thermal reactions of a cyclic olefin, isotetralin (ISO), with aromatics, anthracene (ANT) and pyrene (PYR). These reactions completed a set of experiments with hydrogen-rich species and aromatics previously reported that included cycloalkanes of perhydropyrene (PHP) and perhydroanthracene (PHA), hydroaromatic donors, tetralin (TET) and dihydroanthracene (DHA), cyclic olefins, hexahydroanthracene (HHA) and ISO, and aromatics, PYR and ANT. Catalytic reactions performed this quarter used a sulfur catalyst that had been shown by Rudnick to affect the hydrogen transfer from cycloalkanes to aromatics and/or coal. Rudnick investigated the dehydrogenation of alicyclic compounds converting them to the corresponding aromatic compounds in a process in which the alicyclic compounds served as hydrogen donors. Thiophenol and thiol were effective catalysts and helped promote the conversion of alicyclic compounds to aromatic compounds. The research performed in our laboratory focused on evaluating the effect of a sulfur catalyst on the transfer of hydrogen from cycloalkanes like perhydropyrene (PHP) to aromatics like anthracene under catalytic conditions. The catalyst used in this study was sulfur generated from thiophenol present at a concentration level of 2000 ppm of sulfur. The reactions were performed under two temperature conditions, 380 and 440{degrees}C; both thermal and catalytic reactions were performed for comparison. In addition, the individual cycloalkane and aromatic compounds were reacted under these conditions so that a direct comparison of the effect of temperature and of catalyst on the reaction products formed could be made.
Date: December 31, 1991
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

The use of ethanol to remove sulfur from coal. Final report, September 1991--December 1992; Revision

Description: The initial technical goal in the project was to develop a chemical method for the cost effective removal of both inorganic and organic sulfur from Ohio coals. Verifying and using a process of reacting ethanol vapors with coal under conditions disclosed in U.S. Patent 4,888,029, the immediate technical objectives were to convert a small scale laborative batch process to a larger scale continuous process which can serve as the basis for commercial development of the technology. This involved getting as much information as possible from small scale batch autoclave or fluid bed laboratory reactors for use in pilot plant studies. The laboratory data included material balances on the coal and sulfur, temperature and pressure ranges for the reaction, minimum reaction times at different conditions, the effectiveness of different activators such as oxygen and nitric oxide, the amount and nature of by-products such as sulfur dioxide, hydrogen sulfide and acetaldehyde, the effect of coal particle size on the speed and completeness of the reaction, and the effectiveness of the reaction on different Ohio coals. Because the laboratory experiments using the method disclosed in U.S. 4,888,029 were not successful, the objective for the project was changed to develop a new laboratory process to use ethanol to remove sulfur from coal. Using copper as a catalyst and as an H{sub 2}S scavenger, a new laboratory procedure to use ethanol to remove sulfur from coal has been developed at Ohio University and a patent application covering this process was filed in March, 1993. The process is based on the use of copper as a catalyst for the dehydrogenation of ethanol to produce nascent hydrogen to remove sulfur from the coal and the use of copper as a scavenger to capture the hydrogen sulfide formed from the sulfur removed from coal.
Date: March 10, 1994
Creator: Savage, R. L.; Lazarov, L. K.; Prudich, M. E.; Lange, C. A. & Kumar, N.
Partner: UNT Libraries Government Documents Department

Resonance Raman and photophysical studies of transition metal complexes in solution and entrapped in zeolites. Progress report, August 1, 1991--March 31, 1992

Description: We have obtained convincing evidence for localization of the optical electron on a single-ring fragment of a chelated ``bipyridine-like`` ligand (ie., pyridylpyrazine or 4-Methyl-bipyridine). In addition we have completed studies of Ru(bipyrazine){sub 3}{sup 2+} in aqueous sulfuric acid (0--98% by weight) and find clear evidence for sequential addition of six-protons to the six peripheral nitrogen atoms. Studies of zeolite-entrapped complexes are continuing and a series of homo- and heteroleptic complexes have been prepared and characterized. Finally, the synthesis of zeolite-entrapped metallophthalocyanines has now been developed and the copper and cobalt analogues synthesized. The characterization of these materials is now in progress.
Date: March 31, 1992
Creator: Kincaid, J. R.
Partner: UNT Libraries Government Documents Department