Cat litter can also be used to absorb moisture in other areas of the home as well. For example, if moisture is an issue at the bottom of trash cans, then sprinkling a layer of cat litter at the bottom of the trash can will help remedy the situation.lay-based litters are the most common and the most cost-effective. For the purpose of absorbing moisture in a room, any cat litter will work, though clay and silica gel cat litters are the most absorbent.