Activated Alumina

Activated Alumina, often used as desiccants, in solid forms of aluminium oxide, also known as AI2O3, in porous spheres, the same minerals that made up our precious ruby and sapphires. It is a highly adsorbent material used in heavy industrial applications for various reasons, such as adsorbing catalysts and removing fluoride and other chemicals. With a high surface area of over 200m2g, the Activated Alumina can adsorb many different substances such as gases and liquids without changing its form and structure, making it the ideal adsorbent for desiccants. It is also commonly used to purify drinking water by filtering fluoride, arsenic, and selenium. This robust nature of the adsorbent makes it perfect for application under high pressure. 

The difference between Activated Alumina and Molecular Sieves is that Molecular Sieves feature pores whose size can be adjusted by exchanging ions, which allows them to separate molecules or substances. On the other hand, Activated Alumina demonstrates a higher water adsorption capability than Molecular Sieves, meaning it can absorb much more water than molecular sieves. Hence, it is used to dry various gases, liquids, and streams.  

Here in Stream Peak, our Activated Alumina comes in two standard sizes, 2-5mm dia and 5-8mm dia, to suit different requirements. With its various properties, such as high water adsorption capacity, mechanical strength, and shallow attrition loss, it is designed to give a dew point of at least -40°C and, in some cases, a dew point of -70°C or better when under high pressure. Contact us for bulk quantities, custom sizes, or special printing requirements.  

Application 

Catalyst 

Activated Alumina can also be used to adsorb catalysts in polyethene production and hydrogen peroxide production. This desiccant also acts as a selective adsorbent to remove arsenic, fluoride, and sulfur from gas streams (Claus Catalyst process). 

Fluoride Adsorbent 

Activated Alumina is mainly used to remove fluoride from drinking water, efficiently reducing fluoride levels from 10.0 ppm (parts per million) to less than 1.0 ppm. The amount of fluoride removed from the filtered water depends on how long the water touches the alumina filter media. The amount of fluoride left in the filtered water decreases with increased Alumina. Lowering the temperature and the pH of the water enables effective filtering. With 5.5 being the ideal pH, it allows for up to a 95% removal rate. 

Vacuum Systems 

Activated Alumina can also be used in high vacuum applications. It works as a charge material in fore-line traps to prevent oil generated by rotary vane pumps from backstreaming into the system. The Activated Alumina can also be regenerated at high temperatures when exposed to moisture over a long period. To restore the adsorbent to its total adsorptive capacity, heat the adsorbent to 150°C – 180°C. The higher the regeneration temperature, the longer the operating cycle and the lower the exit dew point of the gas. It should also not be exposed to a temperature above 350°C for better performance over a long period for the adsorbent. 

To learn more about activated alumina, please visit our blog. Direct purchase is also available from our online store. Contact us for bulk quantities, custom sizes, or special printing requirements.  

 

  • Physical appearance does not change
  • Large surface adsorption area
  • Ideal for use in heavy industrial applications

Activated Alumina Product Brochure: Download