| Abstract
| - A reliable method for adsorption systems in equilibrium is established to derive coverage-dependent kineticsand thermodynamics from the volumetric data obtained during the static microcalorimetric measurement ofheats of adsorption. The Wigner−Polanyi equation is applied to analyze the pressure change as a function oftime during stepwise dosing of the adsorptive until thermodynamic adsorption−desorption equilibrium isestablished. For carbon monoxide adsorption on a hydrogen-reduced Cu/ZnO/Al2O3 catalyst, the adsorptionrate constant (ka) is found to be in the range from 10-6 to 10-4 Pa-1 s-1, and the desorption rate constant (kd)from 10-4 to 10-2 s-1, both increasing with fractional coverage θ. The kinetically derived equilibrium constantK(θ) is in good agreement with K(θ) obtained from the adsorption isotherm. RT ln(Kp0) and the differentialheat of adsorption (qdiff) were found to decrease in parallel, reflecting a normal Temkin-type heterogeneity.
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