STERIC REQUIREMENTS FOR THE SOLVENT SWELLING OF ILLINOIS NO 6 COAL

Steric effects on the kinetics of solvent swelling of Illinois No. 6 coal were examined. The equilibrium swelling values (Q) and initial swelling rates (V) of Illinois No. 6 coal in various solvents were determined by using an instrument recently developed in our laboratory. The steric bulk of the penetrant molecules had a significant effect on coal swelling. For example, the initial swelling rates (V) of coal in n-butylamine, sec-butylamine, isobutylamine, and tert-butylamine were 3.7 x 10(-1), 6.8 x 10(-2), 3.1 x 10(-2), and 6.2 x 10(-3) min-1, respectively. A similar trend was observed with ketones. Experiments were carried out by using commercially available cross-linked synthetic polymers, such as styrene-divinylbenzene copolymers, under the same conditions.