Activated alumina is a highly effective adsorbent in both gas and liquid applications and, as such, is employed by several industries for targeted removal of components from other media. As an adsorbent, activated alumina is most well known for its use in water filtration applications, where it serves as a cost-effective adsorbent for removing fluoride from water. It can also remove various other contaminants, including arsenic, lead, and sulfur.
Like an adsorbent, activated alumina can also adsorb water from the air, allowing it to be used as a desiccant; activated alumina can capture and trap water to keep things dry, much like silica gel. As a desiccant, it can adsorb up to 20% of its weight in water at a relative humidity of 50%. Activated alumina is employed as a desiccant in a wide variety of applications, including the removal of water vapor from gases in industrial settings. Water adsorbed onto it can then be desorbed via thermal treatment, and the alumina reused.
Activated alumina is also widely used as a catalyst, with roles as the catalyst itself and an inert carrier or substrate for other catalysts. As a catalyst, activated alumina is known for its role as a Claus catalyst; activated alumina is the most commonly used Claus catalyst in sulfur recovery endeavors at oil and gas refineries.
