Part II Thermal-Programmed Methods

These methods are significant in applied chemical processes, serving as basis for defining the process conditions, but also in basic studies. There are three main approaches. 

the phenomena occurring on the surfaces, the adsorption, desorption, and the surface reactions, are fundamental for determining the kinetics and mechanisms of the reactions in chemical processes. It is also a way to identify active sites and determine the nature and strengths of adsorption-desorption on surfaces. 

Second, one needs to know the structure of the catalyst, the oxidation states, and the interaction between the metal and the support, besides the degree of reduction or oxidation of oxides or metals, respectively. Finally, for the activation process of the catalysts, gases, such as H2, O2, CO, and CH4, or other molecules, like H2S and CS2, are used for sulfidation. These techniques with temperature programming allow predicting the conditions used in an industrial process. 

by using these techniques, determine the conditimis for the decomposition of the precursors during the preparation of the catalyst and the identification of coke, poisons, or impurities after reaction, in addition to the possibility of removing these compounds. 

The programmed temperature techniques may be performed by gravimetric and volumetric methods, which will be treated in the following order of subitems  

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