How to Recharge Silica Gel

Those nifty packets you find tucked inside your new pair of shoes are filled with silica gel, a granular desiccant that removes moisture, protecting the item from damage. This high-capacity adsorbent is available in loose or packet form and can absorb up to 40 percent of its weight in moisture. Overtime, however, the silica gel can lose its moisture-removing power and become ineffective. When this occurs, don't throw the silica gel out: recharge or dry it with heat so you can continue to use it.

Silica gel is a form of silicon dioxide, a naturally occurring mineral. (Image: ajt/iStock/Getty Images)

Things You'll Need

  • Baking sheet

  • Aluminum foil

  • Airtight container

  • Microwave safe container

  • Spoon

Oven Method

Step 1

Preheat an oven to 275 degrees Fahrenheit. Line a baking sheet with aluminum foil.

Step 2

Lay the silica gel packets flat on the foil-lined baking sheet. For loose silica gel, spread the granules in a layer no more than 2 inches thick on the foil-lined baking sheet.

Step 3

Place the baking sheet inside the preheated oven and bake for several hours. The amount of time varies between 1 to 12 hours depending on the thickness of the silica gel. A good general rule of thumb is baking for 1 ½ hours for every 30 ounces of silica gel.

Step 4

Remove the baking sheet from the oven. Let the silica gel cool to room temperature on the baking sheet.

Step 5

Store the cooled silica gel packet in an airtight container until you're ready to use it.

Microwave Method

Step 1

Place the silica gel in a microwave safe container. Set the container inside the microwave.

Step 2

Heat the silica gel for three to five minutes on medium to medium high.

Step 3

Examine the silica gel for color change, which will occur when it is recharged or dry. If it is not dry, stir with a spoon and place back into the microwave for an additional three to five minutes.

Step 4

Continue checking it for color change and microwaving for three to five minutes until the gel is dry. Let the silica gel cool to room temperature in the microwave-safe container.

Tip

Wear an oven mitt when removing the baking sheet from the oven.

Warning

Never handle silica gel immediately after drying; it can get very hot in the oven or microwave.

References & Resources