23 research outputs found
Chemistry and catalysis of coal liquefaction: catalytic and thermal upgrading of coal liquid and hydrogenation of Co to produce fuels. Quarterly progress report, October-December 1983
Results from 5 ongoing research tasks are reported. (LTN
Chemistry and catalysis of coal liquefaction catalytic and thermal upgrading of coal liquid and hydrogenation of CO to produce fuels. Quarterly progress report, January-March 1984
Coal-derived liquids are characterized by the presence of a considerable concentration of oxygen-containing components. Therefore, a systematic catalytic hydrodeoxygenation (HDO) study of coal-derived liquids and related model compounds is being carried out. This study provides information not only on the mechanism of HDO as related to the subject of catalytic upgrading of coal-derived liquids, but also on the role of oxygen-containing compounds in primary coal liquefaction processes. The main objective of this research project is to develop effective catalyst systems and processing conditions for hydrodenitrogenation (HDN) of coal-derived liquids (CDL) in a wide range of nitrogen contents and structural type composition. This is of particular importance in view of the higher concentration of nitrogen-containing compounds in CDL as compared to that in petroleum feedstocks. For a better understanding of denitrogenation processes, the project includes systematic denitrogenation studies not only of CDL but also of related model N-containing compounds found in such liquids, e.g., phenanthridine, 1,10-phenanthroline, carbazoles, acridines, etc., as a function of catalysts type and experimental rate, mechanism and stereochemistry of HDN of structurally distinct N-containing aromatic systems in the presence of sulfided catalysts
Concepts of fundamental processes related to gasification of coal. Quarterly progress report, July-September 1981
The research projects are described: (1) single stage catalytic coal gasification is an attractive concept as a direct method of producing high BTU gas from coal. This process involves the introduction of a coal-solvent slurry and hydrogen gas into a fixed bed catalytic reactor, which employs a catalyst high in hydrogenation and cracking activity. Steam may also be added to the system. The gas produced will be principally methane. Thermodynamic calculations indicate that this process is essentially autothermal. Since this process utilizes the heat of methanation to a maximum extent, significant overall energy savings can be achieved over the more conventional multi-stage gasification systems. The primary objective of this research is to optimize the process variables to maximize methane yields. Initially, a sulfided Ni-W/SiO/sub 2/-Al/sub 2/O/sub 3/ catalyst will be used; (2) the demand for molecular hydrogen and for synthesis gas is rapidly increasing. Therefore, an extensive program on steam reforming of aromatic compounds such as benzene, substituted benzenes, naphthalene and other aromatics found in coal and coal-derived liquids (CDL) is being carried out. The combination of coal liquefaction-steam reforming of CDL could prove to be an important alternative to coal gasification for the production of SNG and hydrogen. An objective of this project is to assess the feasibility of this alternative. Potentially, coal liquids could be reformed directly in a single step to high BTU gas
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High conversion of coal to transportation fuels for the future with low HC gas production. Progress report, October 1, 1995--December 31, 1995
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 a 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 system, at a size sufficient to evaluate the process concept for production of transportation fuels from coal
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High conversion of coal to transportation fuels for the future with low HC gas production. Progress report No. 14, January 1--March 31, 1996
The objective of this project is to produce a synthetic crude from coal at a cost lower than $30.00 per barrel (Task A). A second objective, reflecting a recent change in direction in the synthetic fuels effort of DOE, 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 system, at a size sufficient to evaluate the process concept for production of transportation fuels from coal. A continuous system has been constructed and operated, with a one-half inch inside diameter (ID) tube as the reaction vessel. As the work in this project proceeded toward its conclusion, an unexpected benefit was discovered. As the residence times were decreased to values of 10 seconds or less, ratios of liquids/HC gases of 20/1 or higher were achieved. But very importantly, it was discovered that the chemical reactions which produce the primary liquids can be carried to high conversions at pressures much lower than reported, and indeed required, in the processes at longer times
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Novel process for depolymerization of coal to C sub 2 -C sub 4 hydrocarbons
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Fundamental studies in production of C[sub 2]-C[sub 4] hydrocarbons from coal
The following conclusions can be drawn from the result obtained in this kinetic study of single stage coal gasification to hydrocarbon (HC) gases high in C[sub 2]-C[sub 4] hydrocarbons. It was observed that the direct conversion of coal to HC gases involves two steps. The first step is thermal cleavage of the coal structure to produce liquids with small amounts of gases and coke. The second step is conversion of liquids to gases. Coal to liquids occurs very rapidly and was completed within 10 minutes. Liquids to gases is the rate-determining step of the overall process. The conversion of liquids to gases was observed to follow first order kinetics. The first order kinetics treatment of the data by isothermal approximation gave an apparent activation energy of approximately 23 kcal/mol. The first order kinetics treatment of the data by a more rigorous non-isothermal method gave an activation energy of 26 kcal/mol. The quantity of HC gases produced directly from coal reached a constant value of about l0% of the dmmf coal at a reaction time of 10 miutes. Most of the HC gases were produced from the liquids. The study of model compounds shows that conversion of liquids to HC gases.proceeds through a carbonium ion mechanism, and this accounts for the production of C[sub 2]-C[sub 4] gases. Liquid to gases occurs by a catalytic hydrocracking reaction
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High conversion of coal to transportation fuels for the future with low HC gas production. Progress report No. 11, April 1--June 30, 1995
The objectives of this research are: (1) produce a synthetic crude from coal at a cost lower than $30.00 per barrel; and (2) 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. Experimental coal liquefaction studies conducted in a batch microreactor in our laboratory have demonstrated potential for high conversions of coal to liquids with low yield 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 system, at a size sufficient to evaluate the process concept for production of transportation fuels from coal. A continuous-flow reactor system is to be designed, constructed and operated. The system is to be computer-operated for process control and data logging, and is to be fully instrumented. The primary liquid products will be characterized by GC, FTIR, and GC/MS, to determine the types and quantities of the principal components produced under conditions of high liquids production with high ratios of liquids/HC gases, hydrogen consumption for the conversion to primary liquids will be calculated. Conversion of the aromatics of this liquid product to isoparrafins will be investigated, to examine the potential for producing a transportation fuel from coal with satisfactory octane rating but low in aromatic content. Progress to date is described
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Novel process for depolymerization of coal to C[sub 2]-C[sub 4] hydrocarbons
Experiments for conversion of coal to light hydrocarbon gases in a single stage have been conducted in a batch reactor. Experiments were performed at five temperatures, ranging from 440 to 500[degrees]C. A dual-functional catalyst was used, consisting of sulfided nickel-molybdenum supported on alumina, mixed with silica-alumina cracking catalyst. Representative data from those experiments are presented below. They reveal why it appeared necessary to perform experiments in a two-stage reactor system before an optimum prototype system could be designed. In Figure 1, it is observed that the production of liquids from coal, at all of the temperatures presented, occurs rapidly, reaching maximum values in less than five minutes. By contrast, Figure 2 reveals that production of hydrocarbon (HC) gases proceeds much more slowly, and continues throughout the time period of the experiment (60 minutes). Figure 3, containing data for conversion at 500[degrees]C, reveals that the continued production of HC gases is accompanied by a corresponding reduction in liquids, indicating that perhaps most of the HC gases are produced from cracking of the liquids. Figure 4 reveals that, at a temperature of 500[degrees]C, most of the HC gases are in fact produced from the liquids
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High conversion of coal to transportation fuels for the future with low HC gas production. Progress report Number 10, January 1--March 31, 1995
An objective of the Department of Energy in funding research in coal liquefaction, 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 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 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 one may approach these results in a continuous-flow system, at a size sufficient to evaluate the process concept for production of transportation fuels from coal. A continuous-flow reactor system is to be designed, constructed and operated. The system is to be computer-operated for process control and data logging, and is to be fully instrumented. The primary liquid products will be characterized by GC, FTIR, and GC/MS, to determine the types and quantities of the principal components produced under conditions of high liquids production with high ratios of liquids/HC gases. From these analyses, together with GC analyses of the HC gases, hydrogen consumption for the conversion to primary liquids will be calculated. Conversion of the aromatics of this liquid product to isoparaffins will be investigated. Results to date on both tasks are presented