Hydrogen transfer reactions in coal liquefaction
Hydrogen transfer reactions occurring in donor solvent coal liquefactions were investigated by studying the reactions of model compounds representing linkages and functional groups found in coal. Dibenzyl (1), dibenzyl ether (2), benzyl phenyl sulfide (3), o-hydroxydiphenylmethane (4), acetophenone (5), and benzaldehyde (6), were used as model acceptors. The H donating capability of tetrahydroquinoline (A) was compared to that of tetralin (B). The role of molecular H and catalytic properties of residue from a solvent refined coal plant on these reactions were studied. The effect of (A) content of liquefaction solvents on the liquefaction of a high volatile bituminous (Powhatan number 5) coal was investigated. Hydrogenated phenanthrene (I), process derived solvent-refined-coal solvent (II), and anthracene oil (III) were used as solvents. Experiments were conducted in a batch autoclave, under the conditions of liquefaction preheaters and dissolvers. (A) was a better H donar than (B). (3), (5), and (6) reacted faster in (A) than in (B). The rates of reactions of (1) and (4) were identical in (A) and (B). However, they abstracted H perferentially from (A) when both these donors were present simultaneously. (2), (3), (5), and (6) reacted faster in the presence of molecular H indicating its direct role in these reactions. There was no effect of H pressure on the reaction of (4). Solvent refined coal residue showed a small catalytic activity towards the reactions of (2), (3) and a relatively larger activity towards the reaction of (5). Addition of (A) to (I) and (II) did not affect the product distribution obtained in the liquefaction of the Powhatan number 5 coal. However, an addition of (A) to (III) led to a net consumption of solvent giving very high yields of asphaltenes, indicating the occurrence of adduction reactions.
- OSTI ID:
- 6421330
- Resource Relation:
- Other Information: Thesis (Ph. D.)
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
COAL LIQUEFACTION
HYDROGEN TRANSFER
BITUMINOUS COAL
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
COMPARATIVE EVALUATIONS
ORGANIC COMPOUNDS
ORGANIC SOLVENTS
RESIDUES
TETRALIN
AROMATICS
BLACK COAL
CARBONACEOUS MATERIALS
COAL
ENERGY SOURCES
FOSSIL FUELS
FUELS
HYDROCARBONS
KINETICS
LIQUEFACTION
MATERIALS
REACTION KINETICS
SOLVENTS
THERMOCHEMICAL PROCESSES
YIELDS
010405* - Coal
Lignite
& Peat- Hydrogenation & Liquefaction