The Argonne coals do not have an extended inter-connected pore network

PCS-331

The Argonne coals do not have an extended inter-connected pore network
Larsen, J.W.; Wernett, P.C.
ACS Division of Fuel Chemistry Preprints 1992 37(2) 849-855

The sorption of N[sub 2], CO[sub 2], ethane, cyclopropane, cyclobutane, cyclopentane, and cyclohexane has been studied on all of the Argonne Premium coals. For all of the bituminous coals, the CO[sub 2] BET surface areas are as expected and much higher than all of the other molecules studied. Plots of log (moles adsorbate in monolayer) vs. log (cross-section area of adsorbate) are straight lines whose slopes are very steep ([minus]5.5 to 11.6) and inconsistent with the known fractal dimensionalities of the coal pore surfaces. For Zap lignite, the CO[sub 2] BET surface area is 274m[sup 2]/g, while all of the hydrocarbons give lignite surface areas of 8[+-]3m[sup 2]/g. These data are inconsistent with adsorption in an inter-connected pore network. For bituminous coals, the dependence of the amount sorbed vs. molecular diameter is similar to the dependence of diffusivities through glassy polymers on molecular diameter. The authors conclude that the pores in coals are isolated from each other and can only be reached by diffusion through the solid, glassy, macromolecular coal.

1. Upper Freeport,PA (UF)
2. Wyodak-Anderson, WY (WY)
3. Illinois #6 (IL)
4. Pittsburgh #8 (PIT)
5. Pocahontas #3 (POC)
6. Blind Canyon,UT (UT)
7. Lewiston-Stockton, WV (WV)
8. Beulah-Zap, ND (ND)