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Low severity coal liquefaction promoted by cyclic olefins. Quarterly technical progress report, April--June 1996

Description: The goal of this research is to develop a methodology for analyzing the reactivity of cyclic olefins in situ in a high temperature and high pressure infrared cell. Cyclic olefins, such as 1,4,5,8-tetrahydronaphthalene (isotetralin) and 1,4,5,8,9,10-hexahydroanthracene (HHA), are highly reactive donor compounds that readily donate their hydrogen to coal and model acceptors when heated to temperatures of 200{degrees}C and above. These donors are active donors in the low severity liquefaction of coal at 350{degrees}C as shown in the research performed in this project. The infrared studies are being performed in a high temperature infrared cell that was obtained from AABSPEC. Modifications to that cell have been made and have been reported in previous progress reports.
Date: December 31, 1997
Creator: Curtis, C.W.
Partner: UNT Libraries Government Documents Department

The single electron transfer chemistry of coals. Final report

Description: This research addressed electron donar properties and radical reactions in coal. Solid residues from pyridine Soxhlet extractions of Pocahontas No. 3, Upper Freeport, Pittsburgh No. 8, Illinois No. 6 and Wyodak coals were exposed to 4-vinylpyridine vapors and swelled. All of the 4-vinylpyridine could not be removed under vacuum at 100{degree}C. Diffuse reflectance FTIR revealed the presence of poly-(4-vinylpyridine) in the Illinois No. 6 and Wyodak coals. EPR spectra displayed the loss of inertinite radicals in Upper Freeport, Illinois No. 6 and Wyodak residues after exposure to 4-vinylpyridine. There was little change in the vitrinite radical density or environment. The molecule N,N{prime}-Diphenyl-p-phenylene diamine (DPPD) was exposed to the solid residues from pyridine Soxhlet extractions of the above coals. Diffuse reflectance FTIR failed to detect the imine product from radical reaction with DPPD. EPR spectra displayed the loss of inertinite radicals in Upper Freeport and Wyodak residues. 7,7,8,8-Tetracyanoquinodimethane (TCNQ) and Tetracyanoethylene (TCNE) were deposited into coals in pyridine. FTIR indicated complete conversion of TCNQ to a material with a singly occupied LUMO. In TCNE the LUMO is about 30% occupied. TCNQ and TCNE were deposited into the pyridine extracts and residues of Illinois No. 6 and Pittsburgh No. 8 coals. Only a small amount of the TCNQ and TCNE displayed nitrile shifts in the IR spectrum of a material with an occupied LUMO. It has been concluded that TCNQ must be part of the aromatic stacks in coal and the TCNQ LUMO is part of an extended band.
Date: December 31, 1994
Creator: Larsen, J.W. & Flowers, R.A. II
Partner: UNT Libraries Government Documents Department

Effect of tetralin on the degradation of polymer in solution

Description: The effect of a hydrogen-donor solvent tetralin on thermal degradation of poly(styrene-allyl alcohol) in liquid solution was investigated in a steady-state tubular flow reactor at 1000 psig at various tetralin concentrations, polymer concentrations, and temperatures. The experimental data were interpreted with continuous- mixture kinetics, and rate coefficients determined for the specific and random degradation processes.
Date: December 31, 1995
Creator: Madras, G.; Smith, J.M. & McCoy, B.J.
Partner: UNT Libraries Government Documents Department

Low severity coal liquefaction promoted by cyclic olefins. Quarterly report, October 1995--December 1995

Description: The goal of this research is to develop a methodology for analyzing the reactivity of cyclic olefins in situ in a high temperature and high pressure infrared cell. Cyclic olefins, such as 1,4,5,8-tetrahydronaphthalene (isotetralin) and 1,4,5,8,9,10-hexahydroanthracene (HHA), are highly reactive donor compounds that readily donate their hydrogen to coal and model acceptors when heated to temperatures of 200{degrees}C and above. These donors are active donors in the low severity liquefaction of coal at 350{degrees}C as shown in the research performed in this project. The infrared studies are being performed in a high temperature infrared cell that was obtained from AABSPEC. Modifications to that cell have been made and have been reported in previous progress reports. During this last quarter the useful temperature range of the high temperature infrared cell was extended to 230{degrees}C through the use of a high-boiling perfluorocarbon solvent. The solvent used was an Air Products and Chemicals Company proprietary product trade named Multifluor APF-240. Solubilities of aromatics and cyclic olefins were quite low in APF-240, usually less than 0.1 wt% at room temperature, but were found to be a strong function of temperature, increasing markedly when the mixtures were heated to 65{degrees}C. Spectra have been obtained of n-hexadecane and naphthalene at temperatures of 65, 100, 125, 150, 175, 200 and 230{degrees}C. This demonstration of the safe operation of the high temperature IR cell and the acquisition of spectra at elevated temperatures paves the way for kinetic studies of the hydrogen donor capability of isotetralin. A perfluoroether has been obtained from Dupont which should extend the useful temperature range of the high temperature IR cell to 350{degrees}C.
Date: December 31, 1995
Creator: Curtis, C.W.
Partner: UNT Libraries Government Documents Department

Exploratory Research on novel coal liquefaction concept. Technical progress, October 1--December 31, 1995

Description: The purpose of this coordinated research program is to explore a new approach to direct coal liquefaction in which the primary coal dissolution step is effected by chemical rather than thermal cleavage of bonds in the coal. This is done at a temperature which is significantly lower than that typically used in conventional coal liquefaction. Reaction at this low temperature results in high conversion of the coal to a solubilized form, with little hydrocarbon gas formed, and avoids the thermally induced retrograde reactions which are unavoidable in conventional thermal processes. In addition, for low-rank coals, a substantial portion of the oxygen in the coal is removed as CO and CO{sub 2} during the dissolution. The higher selectivity to liquid products and rejection of oxygen as carbon oxides should result in improved hydrogen utilization. The basis of this novel concept is the discovery made by CONSOL R&D that certain hydride transfer agents are very active for coal dissolution at temperatures in the range of 350{degrees}C. Activities during this quarter were conducted under Tasks 2 and 5. The Task 2 work was concentrated on evaluating the effects of first-stage reaction variables on coal conversion using the microautoclave, construction of a 1L reactor system for producing large quantities of first-stage reaction products, microfiltration tests with the first-stage products, and trial operation of the second-stage hydrotreater. Task 5 work was concentrated on the literature survey and defining the cost of production of the hydride ion reagent.
Date: December 31, 1995
Creator: Burke, F.P.; Winschel, R.A. & Brandes, S.D.
Partner: UNT Libraries Government Documents Department

Progress in donor assisted coal liquefaction: Hydroaromatic compound formation

Description: The role of hydrogen donor compounds in coal liquefaction has been extensively investigated since the mid 1960`s using model compounds and process derived hydrogen donor solvents. Our recent research and that of other investigators have shown that two model compounds in particular have great efficacy in solvating low rank coals. 1,2,3,10b tetrahydrofluoranthene (H{sub 4}Fl) and 1,2,3,6,7,8 hexahydropyrene (H{sub 6}Py) have been used to dissolve Wyodak coal to > 95% soluble material as measured by tetrahydrofuran (THF). Although these hydrogen donors are very effective, they may not be found in any significant concentrations in actual liquefaction process recycle solvents. Therefore, studies with process derived recycle materials are necessary to understand donor solvent chemistry. The objective of this paper is to present results of solvent hydrogenation experiments using heavy distillate solvents produced during testing at the Wilsonville Advanced Coal Liquefaction Test Facility. We evaluated the impact of hydrogenation conditions upon hydrogen donor formation in process derived distillates and compared these process derived solvents with the highly effective H{sub 4}Fl and H{sub 6}Py donors in coal liquefaction tests. This paper presents data on reaction conditions used for distillate hydrotreating and subsequent coal liquefaction, with an aim toward understanding the relationship between reaction conditions and donor solvent quality in recycle distillates.
Date: December 31, 1993
Creator: Kottenstette, R. J. & Stephens, H. P.
Partner: UNT Libraries Government Documents Department

Coal-derived promoters for the liquefaction of Illinois coal. Technical report, September 1, 1991--November 30, 1991

Description: The objective of this program is to investigate the use of liquids derived from coal either by mild gasification or supercritical extraction (SCE) to promote direct liquefaction of Illinois coal. Some organic sulfur-, nitrogen-, and oxygen-containing compounds have been found to enhance liquefaction reactions. The use of Illinois coal to produce liquid fractions rich in these types of compounds could increase the rates of liquefaction reactions, thus improving the process economics. An integrated process combining direct liquefaction with mild gasification or SCE of coal is being developed by IGT. The approach taken in this two-year program is to use recently developed molecular probe techniques to assess the reactivity of three coal-derived liquids with respect to (A) hydrogen transfer rate, (B) carbon-carbon bond cleavage rate, (C) free radical flux, and (D) hydrocracking activity. Sample liquids from Illinois Basin Coal IBC-106 are prepared by three methods: mild gasification in an isothermal free-fall reactor (IFFR), steam treatment followed by mild gasification in a fixed-bed reactor (ST/FBR), and SCE using toluene in a batch autoclave. During the first year of the program, the IFFR and ST/FBR coal liquids were produced and characterized, and the IFFR liquid was assessed by the four molecular-probe methods. During the first quarter of the second year, reactivity testing and data analysis on the ST/FBR coal liquid was completed. For the ST/FBR liquid, hydrogen transfer rate showed a mean increase of 7%, C-C bond cleavage selectivity increased by 27%, free radical flux increased 101%, and data indicated a 227% increase in hydrocracking activity. 12 refs., 5 figs., 7 tabs.
Date: December 31, 1991
Creator: Carty, R. H.
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

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

Description: Goal this quarter was to evaluate the reactivity of an anthracene (H-deficient aromatic) and perhydropyrene (H-rich cycloalkane) system to determine if this system is the one desired for the parametric evaluation. Idea was to determine if hydrogen could be transferred from cycloalkane to aromatic in a hydrogen atmosphere, which is always present in coprocessing. This quarter`s work established procedures for performing thermal and catalytic reactions without a solvent, and for analysis of reaction products. Individual thermal and catalytic reactions using anthracene and perhydropyrene were the primary reactions performed this quarter.
Date: December 31, 1992
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

The role of the resid solvent in coprocessing with finely divided catalysts. Quarterly report, October--December 1993

Description: The reactions with anthracene as a hydrogen acceptor were performed to determine how much hydrogen could be transferred by the hexane soluble resid fraction and hydrogen atmosphere to anthracene. The product distributions obtained by anthracene are given in Table 4. The products obtained from anthracene (ANT) were dihydroanthracene (DHA) and hexahydroanthracene (HHA). When FHC-365 was the resid used in the reaction, very similar amounts of ANT, DHA, and HHA were present after the reaction in both the catalytic and noncatalytic reaction. The predominant product was DHA at 51 to 53 mol%. Slightly more than one-fourth of the ANT remained unreacted. The production of HHA was between 20 and 22%. The amount of H{sub 2} accepted by ANT was the same for both catalytic and noncatalytic reactions. For the reactions with Maya, ANT reacted differently under noncatalytic and catalytic conditions. The reaction products produced were DHA and HHA, with DHA being the predominant product. In the catalytic reaction, substantially more DHA was produced under catalytic conditions and substantially less ANT remained than in the noncatalytic reaction. Under both reaction conditions nearly the same amount of HHA was produced. Under catalytic conditions, nearly twice as much hydrogen was accepted by ANT than under noncatalytic conditions. The product distribution from ANT obtained for the noncatalytic reaction with Maya was similar to dig obtained from ANT when ANT was reacted with FHC-365. The catalyst only seemed to have an effect with Maya resid. The catalyst also had a strong effect on the GC fraction obtained from the reaction using hexane solubles of Maya with ANT. The average boiling point showed a substantial shift toward low boiling constituents.
Date: December 31, 1993
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

Low severity coal liquefaction promoted by cyclic olefins. Quarterly report, October--December 1993

Description: Acid pretreatment removes those alkaline metal and alkaline earth cations which inhibit coal reactivity and hydrogen transfer. Shams et al. (1992) found that through this pretreatment a large portion of the calcium present in coal was removed. Hydrochloric acid was used in that study, but sulfurous acid, if similar results are achieved, would be a much more suitable acid for processing. Another pretreatment method to remove these cations is one using ammonium acetate (Hengel and Walker, 1984). This study will evaluate the effect of combining these two principles, acid pretreatment of coal and rapid hydrogen transfer, for improving hydrogen transfer under low severity conditions. The acid pretreatment methods showed more success with low rank, subbituminous coals and lignite. Therefore, Wyodak subbituminous coal (WY) from the Argonne Premium Sample Bank and Black Thunder subbituminous coal (BT) from Amoco are being used and compared in this study. The cyclic olefin, 1,4,5,8-tetrahydronaphthalene (isotetralin, ISO) and its analogue, 1,2,3,4-tetrahydronaphthalene (tetralin, TET), will also be used and compared in this study. The efficacy of the two-ringed ISO can then be compared with the previously studied three-ringed HHA. Dr. James Hool, Professor of Industrial Engineering and an expert in statistics and experimental design, assisted in formulating the four-dimensional experimental matrix found in Figure 1. It is through this parametric analysis that the effect of each factor in this pretreatment and low severity liquefaction system will be determined.
Date: December 31, 1993
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

Low severity coal liquefaction promoted by cyclic olefins. Quarterly report, July--September 1993

Description: Low-severity coal liquefaction allows for the solubilization of coal with reduced gas make. The idea being tested in this research is whether selective bond rupture occurs during liquefaction at low temperatures that can be satisfied by hydrogen donation from highly active hydrogen donor compounds. Promotion of coal solubilization through hydrogen transfer using highly active and effective hydrogen donors is the objective of this study. The highly effective hydrogen donors being tested are cyclic olefins. Representative cyclic olefins are isotetralin (ISO), which is 1,4,5,8-tetrahydronaphthalene, and 1,4,5,8,9, 10hexahydroanthracene (HHA). These compounds have been shown to highly effective donors (Bedell and Curtis, 1991) which release their hydrogen at fairly low temperatures, in the 200 to 300{degrees}C range. ISO has been shown to be much more effective than its hydroaromatic analogue tetralin (TET) in releasing hydrogen at low temperatures and transferring that hydrogen to an acceptor molecule or to coal (Bedell and Curtis, 1991). Likewise, at 380{degrees}C, the ability of HHA to release hydrogen in both N{sub 2} and H{sub 2} atmospheres was greater than a comparative hydroaromatic compound, dihydroanthracene (DHA). However, when an acceptor molecule or coal was present, DHA was as or more active than HHA in transferring hydrogen (Bedell et al., 1993). In another study, at equivalent reaction conditions and in the presence of anthracene (ANT) as a hydrogen acceptor, ISO released more than 200 times as much hydrogen as TET and HHA released 18 to 25 times as much hydrogen as DHA (Wang, 1992).
Date: December 31, 1993
Creator: Curtis, C. W.
Partner: UNT Libraries Government Documents Department

Resonance Raman and photophysical studies of transition metal complexes in solution and entrapped in zeolites

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

Coal-derived promoters for the liquefaction of Illinois coal. Final technical report, September 1, 1991--August 31, 1992

Description: The objective of this program was to investigate the use of liquids derived from coal either by mild gasification or supercritical extraction (SCE) to promote direct liquefaction of Illinois coal. In this two-year program recently developed molecular probe techniques were used to assess the activity of three coal-derived liquids with respect to accelerating (A) hydrogen transfer, (B) carbon-carbon bond cleavage, (C) free radical flux, and (D) hydrocracking activity. Three sample liquids were prepared from IBC-106 coal by: mild gasification in an isothermal free-fall reactor (IFFR), steam treatment/mild gasification in a fixed-bed reactor (ST/FBR), and SCE using toluene. For comparison, tests were also performed on a Wilsonville recycle solvent (RS) and on benzyl phenyl sulfide (BPS), a ``benchmark`` promoter. Sample/blank pairs were tested at 400--425{degrees}C in laboratory microreactors, and effectiveness was based on the increase in extent of a key reaction for each sample containing coal liquid, compared to its blank. In general, the IFFR liquid was the most effective liquid for promoting hydrogen transfer (+21%) and free radical flux (+107%), while the SCE liquid was the most effective promoter of C-C bond cleavage selectivity (+119%) and hydrocracking (+359%). The ST/FBR liquid was slightly less effective than the IFFR liquid in all categories. BPS was used primarily to validate the adequacy of the methods.
Date: December 31, 1992
Creator: Carty, R. H. & Knight, R. A.
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

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, 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. 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

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

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

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

Selective solvent absorption in coal conversion. Quarterly report, July 1, 1992--September 30, 1992

Description: The objectives of this program include: Determine the importance of the presence of added hydrogen donor compounds within the coal in the first stage of direct liquefaction processes; and to determine the composition of the solvent absorbed by and present within the coal in the first stages of direct coal liquefaction. The scope includes the study of the conversion of Argonne Premium coals in tetralin and 2-t-butyltetralin and a comparison of the following: Conversion to soluble products and product composition. Hydrogen donated by both solvents will be measured by gas chromatography and the same technique will be used to establish the amount of dealkylation of 2-t-butyltetralin. Reactions will be performed at several different temperatures for varying amounts of time.
Date: December 31, 1992
Creator: Larsen, J. W. & Amui, J.
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

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