Table 5. Fitting Results of Langmuir and BET Models to the CO2 Adsorption Data.
| Langmuir
model fit |
BET
model fit |
|||||||
|---|---|---|---|---|---|---|---|---|
| sample | parameter, b (Pa–1) | maximum adsorption capacity, m∞ (g of CO2/kg of coal) | standard Gibbs free energy, ΔGad0 (kJ/mol) | energy of adsorption ΔHad (kJ/mol) | parameter, c | adsorbed monolayer coverage, nmon (g of CO2/kg of coal) | specific surface area, asp (m2/kg) | Q1–Q2a (kJ/mol) |
| EMB1 EXP1-A | 3.86 × 10–07 | 55.4 | –36.6 | –15.56 | 14.43 | 18.83 | 6.60 | |
| EMB1 EXP2-A | 1.31 × 10–06 | 35.57 | –33.6 | –19.58 | 13.05 | 27.18 | 6.37 | |
| EMB1 EXP1-A+ EXP2-A | 8.54 × 10–07 | 40.4 | –34.6 | –18.21 | 22.67 | 18.16 | 64,826 (for c> 20) | 7.74 |
| EMB2 EXP4-A | 6.20 × 10–07 | 37.9 | –35.4 | –17.57 | 11.0 | 18 | 5.94 | |
| EMB3 EXP5 | 5.74 × 10–07 | 70.7 | –35.6 | –15.86 | 7.78 | 40.34 | 5.08 | |
a
The difference between the energy of adsorption of the first layer and the subsequent liquid layers.