Adsorption microcalorimetry provides the study adsorption kinetics and thermodynamics, but theoretical methods were insufficient to evaluate these processes on energetically heterogeneous surfaces of catalysts. In this work they are established based
on Transition State Theory and uniform energy distribution, and applied to investigate different adsorption systems. On ZnO, CO_2 adsorption revealed the block effect of OH groups; CO adsorption revealed the feature of active sites after various
pretreatments. Their co-adsorption strengthened the adsorption of CO due to the increased Lewis acidity caused by adsorbed CO_2. The interaction of CO with supported gold catalysts consists of CO adsorption on Au and on metal cation, CO oxidation, and
adsorption of CO_2 on supports. Compared with Au/alumina and Au/titania, the Au/ZnO catalyst has the largest amount of removable oxygen, strongest interaction between CO, O_2 and the support, and the weakest interaction between CO and Au.