What are the most common materials used in desiccants?

Desiccants can contain Silica Gel, Montmorillonite Clay, and Molecular Sieve. Silica Gel is capable of adsorbing 40% of its weight in water vapor at 100% humidity. It has the highest capacity of any commercial desiccant for moisture adsorption. Montmorillonite Clay is used in most industrial applications requiring humidity control. Molecular Sieve is the desiccant of choice for the most unique applications. It offers a range of adsorption selectivity based on molecular size.