Liquid Phase Calorimetric Method as a Tool for Acid Strength Measurements and Application to a Variety of Sustainable Catalysts

It has been about 36 years since the first published paper about the calorimetry and adsorption (Cal-Ad) method by Prof. Drago. These separated methods are very old and important characterization tools for different molecules and materials, as recognized in chemistry. The idea of coupling these two techniques arose from the need to have more information about the thermodynamic parameters of a catalyst. The Cal-Ad method provides a measure of the magnitude (K-i), strength (- increment H-i), and quantity (n(i)) of sites present in a catalyst. The original idea is based on the application of the donor-acceptor concept using the Electrostatic Covalent Model, ECW in the areas of catalysis and material chemistry. Particularly, enthalpy measurements of acidity are directly related to the activity of various catalysts in a variety of reactions. Currently, more than twenty-five catalysts have been carefully characterized by this method in addition to spectroscopic and other thermal methods. Thus, this review seeks to present the fundamentals of the method and show different applications of the characterized catalysts for a variety of reactions in order to use these data as an alternative to choose a catalyst for an acid-dependent type reaction.

Automated summary

The calorimetry and adsorption (Cal-Ad) method, which combines two techniques, has been an important tool in chemistry for 36 years. It provides information about the thermodynamic parameters of catalysts, including the number, strength, and size of active sites. This method is based on the donor-acceptor concept and the Electrostatic Covalent Model (ECW), and has been widely applied in catalysis and material chemistry. By characterizing more than 25 catalysts and using spectroscopic and thermal methods, this review demonstrates the various applications of Cal-Ad method for acid-dependent reactions.