Exploratory study of coal-conversion chemistry. Quarterly report No. 4, February 19-May 18, 1982
SRI is conducting a program on the chemistry of the conversion of coal to liquid fuels: Task A deals with mechanisms of donor solvent liquefaction; Task B is a study of the conversion of coal and model compounds in the CO/H/sub 2/O system. In Task A, determination of the products, rates, and mechanisms of central bond scission of diphenyl ether and 1,2-dinaphthylmethane in tetralin, 9,10-dihydroanthracene, and 9,10-dihydrophenanthrene allows us to determine the predominant mechanism of hydrogen transfer to these substrates. Diphenyl ether decomposes in the above three solvents by a radical addition-elimination mechanism, with defined first-order rate constants of approx. 1 x 10/sup -7/, 2 x 10/sup -6/, and 2 x 10/sup -7/ s/sup -1/, respectively. The relative reactivity of the two substrates, the relative reactivity in the three solvents, and the positional preference for hydrogen transfer provide compelling evidence for the previously unreported single-step transfer of hydrogen from a radical to a closed-shell ..pi..-system. Efforts in Task B were concentrated on the conversion of anisole in D/sub 2/O and in tetralin at 400/sup 0/C. Experiments were conducted in two different reactor systems, small glass ampoules and 1/4-in. 316 stainless steel tubes. Benzene and phenol were the major products with the rates of product formation affected by the reaction medium and the reactor walls. The rate of benzene formation was found to be more rapid in D/sub 2/O than tetralin, and somewhat greater in glass ampoules than in stainless steel reactors for 20 min. We also studied the conversion of bibenzyl in D/sub 2/O and in tetralin in stainless steel tubes at 400/sup 0/C. In tetralin, toluene was the major product. In D/sub 2/O, the products were toluene, benzene, diphenylmethane, stilbene, and phenanthrene. A novel hydration scheme is suggested for the reactions of bibenzyl in water.
- Research Organization:
- SRI International, Menlo Park, CA (USA)
- DOE Contract Number:
- AC22-81PC40785
- OSTI ID:
- 5127502
- Report Number(s):
- DOE/PC/40785-4; ON: DE82020736
- Country of Publication:
- United States
- Language:
- English
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Exploratory study of coal-conversion chemistry. Quarterly report No. 6, August 19, 1982-November 18, 1982
Reactions of diphenyl ether with elemental sulfur, hydrogen sulfide and iron sulfides in the presence and absence of hydrogen and carbon monoxide
Related Subjects
COAL LIQUEFACTION
CHEMISTRY
HYDROGEN TRANSFER
ANISOLE
BIBENZYL
CHEMICAL BONDS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CLEAVAGE
EXPERIMENTAL DATA
HEAVY WATER
LABELLED COMPOUNDS
RADICALS
STRUCTURAL MODELS
TETRALIN
WALL EFFECTS
WATER
AROMATICS
CRYSTAL STRUCTURE
DATA
ETHERS
HYDROCARBONS
HYDROGEN COMPOUNDS
INFORMATION
KINETICS
LIQUEFACTION
MICROSTRUCTURE
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
OXYGEN COMPOUNDS
REACTION KINETICS
THERMOCHEMICAL PROCESSES
010405* - Coal
Lignite
& Peat- Hydrogenation & Liquefaction