Coal liquefaction with supercritical solvents

Thesis/Dissertation · Wed Jan 01 00:00:00 EST 1986

OSTI ID:6964091

Deshpande, G V

The effect of density on the liquefaction kinetics of a bituminous coal (Bruceton, experimental mine), in the presence of a non-donor solvent (toluene) is examined. The effects of coal rank and type, and liquefaction solvent are also addressed. Donor solvents like piperidine gas higher conversions than non-donor solvents like toluene or water and heavy incorporation of piperidine is found in the soluble products of coal. The temperature (597-698 K), density (0.15-0.60 g/cc), mode of contact and solvent to coal ratio (6-30) had a significant effect on the product distribution. The stirrer speed and the presence of inerts like argon had no measurable effect on the product distribution. Based upon the experimental results, the following model is proposed. A fraction of coal dissolves instantaneously and this fraction increases with an increase in either the temperature or the density of the supercritical fluid. This dissolved fraction then undergoes pyrolysis reactions to give gasses, oils and asphaltenes and these products undergo retrogressive reactions giving char (THF insoluble products). The presence of a donor solvent or molecular hydrogen prevents the retrogressive reactions and a donor solvent reacts chemically with the coal to give greater yields of THF soluble products. A lumped kinetic model is presented to describe this behavior for the toluene-Bruceton bituminous coal system. This model adequately predicts the product distribution for the entire range of parameters used in this study and is completely consistent with the hypothesized liquefaction mechanism. It clearly shows that higher densities can increase both the reaction rate and the maximum conversion obtained.

• Research Organization: Pittsburgh Univ., PA (USA)
• OSTI ID: 6964091
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
BITUMINOUS COAL
SUPERCRITICAL GAS EXTRACTION
COAL LIQUEFACTION
CHEMICAL REACTION KINETICS
MATHEMATICAL MODELS
ASPHALTENES
CHEMICAL REACTIONS
COAL GAS
COAL LIQUIDS
COAL RANK
COMPARATIVE EVALUATIONS
DENSITY
MIXING
ORGANIC SOLVENTS
PIPERIDINES
PYROLYSIS
TEMPERATURE EFFECTS
TOLUENE
ALKYLATED AROMATICS
AMINES
AROMATICS
ASPHALTS
AZINES
BITUMENS
BLACK COAL
CARBONACEOUS MATERIALS
COAL
DECOMPOSITION
ENERGY SOURCES
EXTRACTION
FLUIDS
FOSSIL FUELS
FUELS
GASES
HETEROCYCLIC COMPOUNDS
HYDROCARBONS
KINETICS
LIQUEFACTION
LIQUIDS
MATERIALS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OTHER ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
PYRIDINES
REACTION KINETICS
SEPARATION PROCESSES
SOLVENT EXTRACTION
SOLVENTS
TAR
THERMOCHEMICAL PROCESSES
010405* - Coal
Lignite
& Peat- Hydrogenation & Liquefaction