Macromolecular coal structure as revealed by novel diffusion tests

Technical Report · Mon Jan 01 04:00:00 EST 1990

DOI:https://doi.org/10.2172/6166199· OSTI ID:6166199

Peppas, N A; Olivares, J; Drummond, R; Lustig, S

The main goal of the present work was the elucidation of the mechanistic characteristics of dynamic transport of various penetrants (solvents) in thin sections of coals by examining their penetrant uptake, front swelling and stress development. An important objective of this work was the study of coal network structure in different thermodynamically compatible penetrants and the analysis of dynamic swelling in terms of present anomalous transport theories. Interferometry/polariscopy, surface image analysis and related techniques were used to quantify the stresses and solvent concentration profiles in these sections. Dynamic and equilibrium swelling behavior were correlated using the polar interaction contributions of the solvent solubility parameters. The penetrant front position was followed in thin coal sections as a function of time. The initial front velocity was calculated for various coals and penetrants. Our penetrant studies with thin coal section from the same coal sample but with different thickness show that within the range of 150 {mu}m to 1500{mu}m the transport mechanism of dimethyl formamide in the macromolecular coal network is non-Fickian. In fact, for the thickest samples the transport mechanism is predominately Case-II whereas in the thinner samples penetrant uptake may be diffusion-controlled. Studies in various penetrants such as acetone, cyclohexane, methanol, methyl ethyl ketone, toluene and methylene chloride indicated that penetrant transport is a non-Fickian phenomenon. Stresses and cracks were observed for transport of methylene chloride. 73 refs., 88 figs., 15 tabs.

• Research Organization: Purdue Univ., Lafayette, IN (USA). School of Chemical Engineering
• Sponsoring Organization: DOE/FE
• DOE Contract Number: FG22-87PC79914
• OSTI ID: 6166199
• Report Number(s): DOE/PC/79914-T12; ON: DE91004165
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010600* -- Coal
Lignite
& Peat-- Properties & Composition
AMIDES
AZINES
CARBONACEOUS MATERIALS
CHEMICAL REACTIONS
CHLORINATED ALIPHATIC HYDROCARBONS
CHLOROFORM
COAL
CRACKS
CROSS-LINKING
DIFFUSION
DOCUMENT TYPES
ENERGY SOURCES
FORMAMIDE
FOSSIL FUELS
FUELS
FURANS
HALOGENATED ALIPHATIC HYDROCARBONS
HETEROCYCLIC COMPOUNDS
MATERIALS
MATHEMATICAL MODELS
METHYLENE CHLORIDE
MOLECULAR STRUCTURE
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
POLYMERIZATION
PROGRESS REPORT
PYRIDINE
PYRIDINES
STRUCTURAL MODELS
SWELLING
TEMPERATURE EFFECTS
TETRAHYDROFURAN