Methods for characterizing the acidic and basic surface sites of coal

Thesis/Dissertation · Tue Jan 01 00:00:00 EST 1985

OSTI ID:6118784

Jones, K L

Flow microcalorimetric, and electrophoretic, methods have been developed for characterizing the acidic and basic surface sites of coal. These studies were done on four coals: (1) a low-ash, high volatile A bituminous coal, (2) a high-ash, high volatile B bituminous sample, (3) a low-ash anthracite, and (4) a high-ash anthracite. During calorimetry, phenol and pyridine penetrated below the external surface region of the coal, as evidenced by appreciable retention times during passage of these sorbates through the coal and by relatively high heats of sorption per unit mass of coal for the first sorption-desorption cycle of a multi-cycle sequence. Tertiary butyl groups attached to phenol and pyridine limited the penetration of these molecules. Molar heats of sorption were more reproducible from cycle to cycle for acetone- and dichloromethane-washed coal samples than for unwashed ones. They were also similar to those for reactions in solution between pyridines and phenols, except for 2,6-di-tert-butyl-substituted probes in which case these molar heats were relatively small because of steric hindrance. Heat of soption per unit mass of coal generally increased after grinding and with increasing mineral matter content, but these trends were not readily apparent in the molar heats of sorption. Also, heat treatment did not appear to appreciably alter molar heats of sorption. Zeta potentials of coal powders in organic acids (dichloromethane, 1,2-dichloroethane, and chloroform) were positive, and in organic bases (acetone and methyl isobutyl ketone) they tended to be negative.

• Research Organization: Lehigh Univ., Bethlehem, PA (USA)
• OSTI ID: 6118784
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
ANTHRACITE
SURFACE PROPERTIES
BITUMINOUS COAL
ADSORPTION HEAT
CALORIMETRY
ELECTROPHORESIS
PHENOL
PYRIDINE
SURFACE POTENTIAL
AROMATICS
AZINES
BLACK COAL
CARBONACEOUS MATERIALS
COAL
ENERGY SOURCES
ENTHALPY
FOSSIL FUELS
FUELS
HETEROCYCLIC COMPOUNDS
HYDROXY COMPOUNDS
MATERIALS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHENOLS
PHYSICAL PROPERTIES
POTENTIALS
PYRIDINES
THERMODYNAMIC PROPERTIES
010600* - Coal
Lignite
& Peat- Properties & Composition