Coal liquefaction model studies: free radical chain decomposition of diphenylpropane, dibenzyl ether, and phenyl ether via. beta. -scission reactions
The thermal decompositions of 1,3-diphenylpropane (1), dibenzyl ether (2), and phenethyl phenyl ether (3) have been found to proceed by free radical chain processes. 1 gave toluene and styrene with a reaction order of 1.55, E/sub A/ = 51.4 kcal/mol, and log A = 12.5. The reaction could be initiated by benzyl phenyl ether but not by 1,2-diphenylethane. 2 gave toluene and benzaldehyde with a reaction order of 1.43, E/sub A/ = 48 kcal/mol, and log A = 12.6. The reaction could be initiated with benzyl phenyl ether. 3 gave phenol and styrene with a reaction order of 1.21, E/sub A/ = 50.3 kcal/mol, and log A = 12.3. The reaction could be initiated by benzyl phenyl ether. All of the data are consistent with free radical chain processes with the reaction order determined by the termination reaction. No evidence for concerted reactions has been found. The thermal chemistry of three-atom links is best described by free radical chain processes. The products are consistent with a free radical chain process involving a ..beta..-scission reaction, and the reaction orders range between first and three-halves order depending upon the nature of the chain termination reaction. Activation parameters are readily estimated from thermochemical kinetic data on the individual reactions with log A approx. = 12 and E/sub A/approx. = 50 kcal/mol. Unlike the one- and two-atom linkages, reactions of the three-atom linkages are promoted by free radical initiators. The potential for inhibition of free radical chains also exists and is currently being studied. 4 tables.
- Research Organization:
- Indiana Univ., Bloomington
- DOE Contract Number:
- AC02-80ER10721
- OSTI ID:
- 5495801
- Journal Information:
- J. Org. Chem.; (United States), Vol. 47:25
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
BENZALDEHYDE
CHEMICAL REACTION KINETICS
CHEMICAL BONDS
CLEAVAGE
COAL LIQUEFACTION
MATHEMATICAL MODELS
ETHERS
PYROLYSIS
ORGANIC COMPOUNDS
STYRENE
TOLUENE
ACTIVATION ENERGY
BENZYL RADICALS
COAL
EXPERIMENTAL DATA
RADICALS
STRUCTURAL MODELS
ALDEHYDES
AROMATICS
ARYL RADICALS
CARBONACEOUS MATERIALS
CHEMICAL REACTIONS
CRYSTAL STRUCTURE
DATA
DECOMPOSITION
ENERGY
ENERGY SOURCES
FOSSIL FUELS
FUELS
HYDROCARBONS
INFORMATION
KINETICS
LIQUEFACTION
MATERIALS
MICROSTRUCTURE
NUMERICAL DATA
ORGANIC OXYGEN COMPOUNDS
REACTION KINETICS
THERMOCHEMICAL PROCESSES
010405* - Coal
Lignite
& Peat- Hydrogenation & Liquefaction