Effects of heavy recycle solvent components on direct coal liquefaction

Conference · Sat Jan 01 00:00:00 EST 1983 · Prepr. Pap., Am. Chem. Soc., Div. Fuel Chem.; (United States)

OSTI ID:6615385

Longanbach, J R

The quality of the recycle solvent is critically important in all direct coal liquefaction processes. The fact that overall solvent quality can be greatly improved by adding some of the lighter nondistillable products to the solvent is one of the most important discoveries in direct coal liquefaction research in recent years. Many recent studies have focused on the role of solvent in direct liquefaction. It has been shown that most hydrogen transferred to the dissolving coal during initial preasphaltene formation comes from the solvent rather than hydrogen gas. The high molecular weight aromatic hydrocarbons in the recycle solvent are particularly adept at transferring hydrogen to coal and can retard retrogressive reactions which can lead to the formation of undesirable insoluble products. On the other hand, the coke formation reactions are also caused in large part by high molecular weight solvent components, particularly those containing phenolics and polyfunctional compounds. Other studies have focused on the role of nitrogen-containing aromatics in the recycle solvent. The lower molecular weight aromatics which contain basic nitrogen have been shown to be excellent hydrogen transfer agents and may also readily penetrate the coal structure to react with reactive coal species before retrogressive reactions can take place.

• Research Organization: Battelle Columbus Laboratories, Columbus, Ohio
• OSTI ID: 6615385
• Report Number(s): CONF-830814-
• Journal Information: Prepr. Pap., Am. Chem. Soc., Div. Fuel Chem.; (United States), Vol. 58:5; Conference: 186. national meeting of the American Chemical Society, Washington, DC, USA, 28 Aug 1983
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
COAL LIQUEFACTION
CHEMICAL REACTION KINETICS
ORGANIC SOLVENTS
CHEMICAL COMPOSITION
HYDROGEN TRANSFER
RECYCLING
SOLVENT PROPERTIES
AROMATICS
ASPHALTENES
COAL
COKE
DISSOLUTION
HYDROCARBONS
MOLECULAR WEIGHT
ORGANIC NITROGEN COMPOUNDS
ASPHALTS
BITUMENS
CARBONACEOUS MATERIALS
ENERGY SOURCES
FOSSIL FUELS
FUELS
KINETICS
LIQUEFACTION
MATERIALS
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
REACTION KINETICS
SOLVENTS
TAR
THERMOCHEMICAL PROCESSES
010405* - Coal
Lignite
& Peat- Hydrogenation & Liquefaction