Results 181 to 190 of about 1,608 (223)
Some of the next articles are maybe not open access.
Recent Progress in the Direct Liquefaction of Coal
Science, 1988Interest in direct coal liquefaction steadily decreased during the 1980s as the price of crude oil dropped; there is now only one integrated coal liquefaction pilot plant active full time in the United States. The economics derived early in the decade established the price of transportation fuels from coal at $80 per barrel or higher.
openaire +2 more sources
The Coal Geochemistry in Direct Coal Liquefaction Technique
2007The coal geochemistry in direct coal liquefaction deals with two factors as following: the reactivity of organic material such as macerals in coal, which will affect the oil yield of the coal liquefaction. The other is the geochemical transmition of metal elements, which will do harm to the environment if not take attention to.
Xiaohong Xia +3 more
openaire +1 more source
Application of Light Microscopy to Direct Coal Liquefaction Research
Microscopy and Microanalysis, 1998Light microscopy was used to analyze the effects of added catalyst at different conditions (temperature and reaction times) in liquefaction testing of a low pyritic sulfur bituminous coal. Quantitative changes in vitrinite/vitroplast reflectance of coal and liquefaction residues were shown to be useful markers in analyzing and understanding the ...
, Irdi, , Warzinski, , Booher
openaire +2 more sources
Catalyst deactivation during direct coal liquefaction: a review
Industrial & Engineering Chemistry Product Research and Development, 1984A review of R and D in catalytic direct liquefaction has shown that catalyst lifetime is more important than initial activity. Deactivation studies indicate that contamination by 20-30 wt% carbonaceous material and 2-8 wt% inorganics results in deactivation best described by the shell progressive deactivation mechanism. Metals contamination is confined
D Thakur, M Thomas
openaire +1 more source
Organic contaminants in direct coal liquefaction — a preliminary assessment
American Industrial Hygiene Association Journal, 1980Area samples taken at two coal liquefaction facilities were analyzed by either gas chromatography or gas chromatography/mass spectrometry to identify the types of organic contaminants to which workers may be exposed. Results indicate that the contaminants consisted primarily of one or two ring low-molecular weight aromatic compounds.
R, Tanita +3 more
openaire +2 more sources
Catalysis in Direct Coal Liquefaction
1992Coal liquefaction can be defined as the conversion of solid coal to products which are liquid at ambient temperatures. Usual methods for direct liquefaction processing are pyrolysis, solvent extraction or hydrogenation. These processes can all be enhanced by the use of catalysts (for example, catalytic pyrolysis or catalytic hydropyrolysis, Exxon Donor
openaire +1 more source
Agglomeration of low-rank coal as a pretreatment for direct coal liquefaction
Fuel, 1992Abstract Laboratory experiments demonstrated that low-rank coals can be cleaned by agglomeration with distillate coal liquefaction recycle oils. Materials tested included a lignite, three subbituminous coals, a bituminous coal, two petroleum oils, and three coal liquefaction recycle oils.
G.A. Robbins +3 more
openaire +1 more source
Kinetic Modeling of Direct Liquefaction of Coal
2016During the past few decades, petroleum has been the main source of liquid fuels. On one hand petroleum reserves are declining, and on the other hand coal reserve is the most abundant fossil fuel known in the world. Liquefaction aims to convert solid coal into liquid fuels. Coal can be converted to liquid and gaseous fuels and chemicals by two different
openaire +1 more source
Improvements in direct coal liquefaction using beneficiated coal fractions
Geological Society, London, Special Publications, 1997Abstract Beneficiated coal fractions from Point of Ayr coal (North Wales) were liquefied in order to determine their effect on conversion, product and metal distribution in coal extract solutions. The coal fractions were obtained in a dense medium cyclone separation unit, using aqueous solutions of Ca(NO 3
J. Barraza, M. Cloke, A. Belghazi
openaire +1 more source
Improvement of Coal Direct Liquefaction by Steam Pretreatment
Energy & Fuels, 1997Pretreatment of coal by reaction with subcritical steam enhances its performance in direct liquefaction. Illinois No.
Olga Ivanenko +3 more
openaire +1 more source