A calorimetric study of the immersion of bituminous coal in liquids

• Main Author: Hollenhead, James B.
• Other Authors: Chemistry
• Format: Others
• Published: Virginia Tech 2014
• Subjects: LD5655.V855 1988.H655; Bituminous coal; Specific heat
• Online Access: http://hdl.handle.net/10919/45157; http://scholar.lib.vt.edu/theses/available/etd-10132010-020048/

The surface properties of coal greatly affect its use in industrial processes such as gasification, liquefaction and the use of coal slurries. In addition, such processes also involve reagent penetration into coal pores and the oxidative state of the coal surface. Reagent penetration into coal was examined by determining the heat and kinetics of immersion of Pocahontas No. 3 coal in water, methanol, a series of n-alkanes, and several cyclic and heterocyclic hydrocarbons. Results indicate that the heat of immersion is sensitive to the carbon chain length of the wetting liquid and its ability to hydrogen bond to coal. The time of immersion is insensitive to carbon chain length but is increased by the presence of nitrogen in a cyclic hydrocarbon. <p>The oxidation of both unextracted and extracted coal at 3200C was followed by immersional measurements in water. The heat of immersion increased rapidly with oxidation time, leveling off after 3 hours of oxidation. Extraction with methanol or pyridine prior to oxidation and immersion lowered the time of immersion in water compared to the unextracted case. The oxidation of coal was also followed by x-ray photoelectron spectroscopy (XPS). The XPS oxygen/carbon ratios correlated linearly with the heats of immersion for the extracted, oxidized coals. Thus, XPS was shown to be a useful ancillary technique to heat of immersion for the study of coal surfaces. === Master of Science