Effect of acid–base properties on design of catalyst for methanol thiolation: A review

Abstract

Reducing the concentration and strength of Lewis acid sites together with increasing the basic properties of catalysts has been found to enhance selectivity toward the desired methanethiol product. Weak acid and strong base Lewis acid–base pairs are the key to catalyst design. A review of the history of research on catalysts shows that the main catalysts that have been studied are metal oxides and zeolites. Alumina was the most important and widely used base for a long period. It was commonly impregnated with alkali metals and tungsten. Nevertheless, newer research studies have proved that alumina can be replaced with TiO2. Tungsten has been found to be ineffective in the design of new catalysts. Furthermore, new research studies have focused on increasing the dispersion of impregnated alkali metals together with manipulating the acid–base properties of catalysts.

Keywords

• Methanol
• Thiolation
• Acid
• Base
• Catalyst