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7. Adsorption under Partially-Saturated Conditions
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ncentration [‐]
Co
1
0.1
0.01
Network model
0.001
ADE
0.0001
0.0 50.0 100.0 150.0
Time [min]
Figure 7.7: The resulting BTC from the network together with the BTC
obtained using the ADE model. Dispersion coefficient values obtained from the
fit to the computed BTCs.
coefficient as a function of saturation for a network with micro-scale distribution
coefficient equal to 1.0.
Figure 7.8: Calculated and fitted values of macro-scale distribution coefficient,
K D, as a function of saturation.
Figure (7.8) shows an increase in the macro-scale distribution coefficient, K D ,
with decrease in saturation, (for a constant micro-scale distribution coefficient
equal to 1.0) resulting from the increase in average specific surface area with
decrease in saturation. There is better agreement between the calculated and
fitted K D values at higher saturations.
We also use a non-equilibrium formulation for describing the macro-scale behavior
of the adsorptive solute. We use the same BTCs computed from the
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