Skip to main content

Avantor Sciences

Silica Gel Reactivation

Information

Question How can I reactivate or regenerate silica gel desiccant that has absorbed moisture?
Answer

    
Silica gel desiccant is available in two primary types, indicating and non-indicating. The indicating property is achieved by impregnation of a moisture sensitive material into the silica gel. Both types of silica gel can be regenerated the same way.

One benefit of silica gel desiccants over zeolites is the ease of regeneration. Since silica gel will release absorbed moisture when heated to temperatures exceeding 212oF it can easily be regenerated in a common laboratory oven or furnace.

To regenerate a silica gel, simply put the gel into a heat resistant container (e.g. glass or metal) and spread it out. Place the silica gel into a oven heated to between 275oF and 300oF. Leave the silica gel in the oven for at least 60 minutes per pound. It is better to heat it longer than to take it out too soon. Remove the silica gel from the oven and allow to cool in a sealed desiccator or glass jar.

One or more of the following factors can affect effective silica gel reactivation:

  • Failure to achieve a uniform temperature of greater than 212oF throughout the entire silica gel batch
  • Failure to provide an adequate supply of hot air to carry away the moisture driven off during reactivation
  • Stopping the reactivation process too soon because the indicator displays an active color
  • Overheating during reactivation can damage the silica gel. Do not exceed 302oF because the silica gel can turn brown or black and the absorption capacity can be affected.
  • Not cooling and storing the reactivated silica gel in a sealed, airtight container
  • Attempting to reactivate silica gel that has been contaminated with oil.

 If you have any questions or require additional information, please contact Technical Services.
Trademarks are owned by Avantor Performance Materials, LLC. or its affiliates unless otherwise noted.
2023 Avantor Performance Materials, LLC.

File CIQA-0106 Silica Gel React Rev. 1.pdf
Keyword 3402, 3401, 4471, 6447, 6551, silica, gel, reactivation,
  • Was this article helpful?