A study of depolymerization and crosslinking reactions in coal liquefaction: Sixth quarterly report for the period December 1, 1986 to February 28, 1987

Technical Report · Thu Jan 01 04:00:00 EST 1987

OSTI ID:6917145

Solomon, P R; Serio, M A; Deshpande, G V

The major goal of this program is to characterize the depolymerization and crosslinking reactions of low rank coals and determine how they can be optimized in liquefaction by combining high heating rates with solvent interactions. Pyrolysis of Zap North Dakota lignite swelled with piperidine and octahydroanthracene separately were carried out in a heated grid reactor at 650/sup 0/C (40 sec) and 800/sup 0/C (15 sec) in vacuum. In the present product analysis system, tar from coal and the solvent in the swelled coal cannot be separated. Hence, as in liquefaction, the tar yields from coal are estimated indirectly. The tar yields are not significantly enhanced due to the presence of piperidine in the swelled coal. With octahydroanthracene as the swelling solvent, the tar yield was not increased over that of untreated lignite at 650/sup 0/C (40 sec). At 800/sup 0/C (15 sec), the tar yield was found to increase due to the presence of octahydroanthracene in the swelled coal. Further work is in progress to quantify this result. The chars of Montana Rosebud subbituminous coal formed in the heated tube reactor were analyzed for crosslink densities by swelling the chars in pyridine. The relative change in swelling ratio correlated very well with CO/sub 2/ plus CH/sub 4/ yield. The same correlation holds good for Zap lignite chars formed in the heated tube reactor and for Pittsburgh Seam bituminous coal in the entrained flow reactor (EFR). It seems that low temperature crosslinking (prior to tar evolution) in subbituminous coals occurs with CO/sub 2/ evolution and high temperature crosslinking (after tar evolution) with CH/sub 4/ evolution. From the study of low temperature decarboxylation kinetics, it was found that, crosslinking in Zap lignite occurred with decrease in the concentrations of the carboxyl and the hydroxyl groups in the lignite. Significant crosslinking in lignites takes place prior to tar evolution. 7 refs., 9 figs., 6 tabs.

• Research Organization: Advanced Fuel Research, Inc., East Hartford, CT (USA)
• DOE Contract Number: FG22-85PC80910
• OSTI ID: 6917145
• Report Number(s): DOE/PC/80910-6; ON: DE87008386
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010405* -- Coal
Lignite
& Peat-- Hydrogenation & Liquefaction
010409 -- Coal
Lignite
& Peat-- Pyrolysis & Carbonization-- (1987-)
ALKANES
AMINES
AZINES
BITUMINOUS COAL
BLACK COAL
BROWN COAL
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CARBONACEOUS MATERIALS
CHALCOGENIDES
CHARS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
COAL
COAL LIQUEFACTION
COAL TAR
CROSS-LINKING
DATA
DECOMPOSITION
DEPOLYMERIZATION
ENERGY SOURCES
EXPERIMENTAL DATA
FOSSIL FUELS
FOURIER TRANSFORMATION
FUELS
HEATING RATE
HETEROCYCLIC COMPOUNDS
HIGH TEMPERATURE
HYDROCARBONS
INFORMATION
INFRARED SPECTRA
INTEGRAL TRANSFORMATIONS
LIGNITE
LIQUEFACTION
MATERIALS
METHANE
NUMERICAL DATA
OPTIMIZATION
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OTHER ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PIPERIDINES
POLYMERIZATION
PYRIDINES
PYROLYSIS
PYROLYSIS PRODUCTS
SPECTRA
SUBBITUMINOUS COAL
SWELLING
TAR
THERMOCHEMICAL PROCESSES
TRANSFORMATIONS
VERY HIGH TEMPERATURE
YIELDS