A study of depolymerization and crosslinking reactions in coal liquefaction: Fifth quarterly report for the period September 1, 1986 to November 30, 1986

Technical Report · Wed Jan 01 04:00:00 EST 1986

OSTI ID:7231163

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. High heating rates are achieved by using a heated tube reactor where coal is heated at about 20,000 C/sec. Solvent interactions to stabilize depolymerization fragments formed at high heating rates are achieved by: (1) co-injection of a donor solvent into the heated tube reactor, (2) preswelling the coal at elevated temperatures and pyrolyzing the swelled coal in the heated grid or heated tube reactors and (3) injecting rapidly preheated coal into a hot solvent. Crosslinking and depolymerization reactions are also being studied by using polymers to simulate the chemistry occurring in coal. During the fifth quarter work was pursued in all of these areas. Slow pyrolysis of Zap lignite at 3 C/min and pyrolysis at temperatures between 50 C and 500 C for reaction time of 24 hours were carried out and the chars analyzed by quantitative FT-IR spectroscopy using the KBr pellet method and by swelling in pyridine to determine crosslink densities. For both sets of samples, a decrease in the swelling ratio due to crosslinking was found to occur with a decrease in carboxyl as well as hydroxyl groups in the char. The chars of Pittsburgh Seam bituminous formed in an entrained flow reactor at 700 C and 800 C and chars of Zap lignite formed in a heated tube reactor at an equilibrium temperature of 800 C were analyzed for crosslink densities by swelling the chars in pyridine. It seems that low temperature crosslinking (prior to tar evolution) in lignites occurs with CO/sub 2/ evolution and high temperature crosslinking (after tar evolution) in bituminous coals occurs with CH/sub 4/ evolution. 4 refs., 10 figs., 1 tab.

• Research Organization: Advanced Fuel Research, Inc., East Hartford, CT (USA)
• DOE Contract Number: FG22-85PC80910
• OSTI ID: 7231163
• Report Number(s): DOE/PC/80910-5; ON: DE87003399
• 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
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 RANK
CORRELATIONS
CROSS-LINKING
DATA
DECOMPOSITION
DEPOLYMERIZATION
ENERGY SOURCES
EXPERIMENTAL DATA
FOSSIL FUELS
FOURIER TRANSFORMATION
FUELS
HEATING RATE
HIGH TEMPERATURE
HYDROCARBONS
INFORMATION
INFRARED SPECTRA
INTEGRAL TRANSFORMATIONS
LIGNITE
LIQUEFACTION
MATERIALS
METHANE
NUMERICAL DATA
OPTIMIZATION
ORGANIC COMPOUNDS
ORGANIC SOLVENTS
OXIDES
OXYGEN COMPOUNDS
POLYMERIZATION
PYROLYSIS
PYROLYSIS PRODUCTS
SOLVENTS
SPECTRA
SWELLING
TEMPERATURE EFFECTS
THERMOCHEMICAL PROCESSES
TIME DEPENDENCE
TRANSFORMATIONS
YIELDS