Zeolite is formed over millions of years as volcanic ash slowly changed and crystallized when exposed to alkaline water. The crystals have an interconnecting lattice structure, forming a honeycomb of interconnecting channels with a negative charge. Within these channels are positively charged ions that attract and trap other materials, including those that cause odors.Because of the honeycomb structure, zeolite is able to absorb moisture and gas molecules that total about 65 percent of the weight of the zeolite itself. The material has virtually no fragrance, and it releases nothing as it absorbs other materials. A day in bright sunshine is usually enough to release the contaminants and restore the zeolite to working condition. Packets can also be recharged in a 200-degree oven for an hour. The low temperature will keep the plastic bags from melting. (Zeolite itself can withstand temperatures of 1,200 degrees Fahrenheit before it degrades.)
Zeolite is a natural mineral which absorbs odors and excess moisture in the air. It can be used as a general deodorizer and to combat mildew or mould. When used in refrigerators and freezers, it can reduce electricity cost by up to 12% by maintaining optimum humidity, and it helps keep food fresher. Zeolite is usually sold in packets that can be hung in strategic locations.