How to Rejuvenate Indicating Bulk Silica Gel and Molecular Sieve
These instructions are meant for indicating (blue or orange) product only, it is difficult to effectively gauge if colorless product has re-generated.
Let’s begin with some safety precautions:
- Use a Pyrex baking dish which is at least a ¼“ thick, the product becomes very hot while drying and potentially can cause other types of glass to shatter.
- It is also recommended not to use a Pyrex pie plate or microwave safe dishes as well.
- Another good option is a metal baking sheet with sides no higher than 2”.
- If you smell a slight odor while re-drying silica gel, the safety data sheets states “oxides of carbon and silicon may be formed when heated”.
- To disperse vapors and or dust coming from the silica gel or molecular sieve use good ventilation in combination with a dust mask from any big box store to prevent inhalation.
- Allow the Pyrex container to cool down to a safe temperature before moving baking dish and use an oven mitt. Set on a trivet or hot pad to absorb any residual heat.
- Before storing the product, allow it to cool well enough to handle than you can transfer to a seal tight container for storage; again do this in a well ventilated area so product dust does not get inhaled.
Now that you are prepared to handle the product safely, there are two options:
Microwave re-drying method:
- Deposit a pound of silica gel or molecular sieve in Pyrex baking dish; spread an even layer in the dish.
- Program the microwave on medium; run it in segments of 3 to 5 minutes at a time.
- Microwave types vary in power so the times listed are approximations.
- Inspect the product for a change in color than stir. Do this over again until you have reached roughly 10 to 12 minutes, which is generally how long it will take to fully rejuvenate.
- Do not overheat, product will darken and become unusable.
Oven re-drying method (preferred):
- Deposit 2 pounds (1 quart) of silica gel or molecular sieve in Pyrex baking dish; spread an even layer in the dish.
- Program the oven at 275°F.
- Leave the oven door slightly ajar and bake for about 1 ½ hours.
- View every 15 minutes for change in color; do not overheat, product will darken and become unusable.
For this and many other product options for controlling moisture, see Delta Adsorbents complete product line.