Silica gel is a desiccant that absorbs and holds outside moisture. The fact that silica gel can hold up to 40 per cent of its weight in excess moisture is what makes it popular. It is used by manufacturers to pack shoes, electronics, and even some food items. Those little packets you find in many of your packages or product boxes contain silica gel, and they are there to make sure that moisture doesn't damage your items. Silica gel is available as loose granules to spread and use for small projects, or in larger canisters to absorb moisture in bigger spaces. Silica gel can last a very long time, because it can be recharged and reactivated.
Preheat the oven to 120 degrees C (250F).
Gather up the silica gel that needs to be reactivated. Spread it out as thinly as possible on a baking tray.
Heat in the oven for five hours. If your silica gel has indicator crystals, heat them until the crystals return to their original colour.
Remove the tray from the oven. Place it into a container that has an airtight seal. Store away from light until you are ready to use again.
Some silica gels can be reactivated in a microwave. This is not the best way to do it, as it can change the quality of the silica gel over time.
Keep silica gel where it will not be accidentally ingested by children.