Activated clay is a naturally occurring porous mineral which has been dried to produce an adsorbent material. The clay has a good adsorption capacity within normal temperature and relative humidity ranges. Activated clay retains its structure as it becomes saturated and can be easily reactivated for re-use by heating.
The main disadvantage of this material is its ability to give up moisture at low temperatures. Subjecting the material to temperatures as low as 50°C may begin the process of releasing moisture back into its surroundings. This property of the material is useful for reactivating the clay but could cause problems for particular applications that are subjected to high temperatures. Therefore care must taken when selecting this material for moisture protection.
Activated clay is chemically inert and non-toxic which makes it safe to handle and can be easily disposed of. The clay is usually more economical than chemically synthesized adsorbents like silica gel or molecular sieves.