As Desiccant:
Calcium chloride's strong ability to absorb moisture makes it an ideal desiccant in the manufacturing process, used to protect goods from moisture damage, especially when transporting and storing sensitive materials. Granular anhydrous calcium chloride is often used as a desiccant to fill drying tubes. Giant kelp (or seaweed ash) dried with calcium chloride can be used in the production of soda ash. Some household dehumidifiers use calcium chloride to absorb moisture from the air. Calcium chloride can also be used as a desiccant or dehydrating agent for gases and organic liquids. Since calcium chloride is neutral, it can dry acidic or alkaline gases and organic liquids. It can also be used to dry small amounts of gases such as nitrogen, oxygen, hydrogen, hydrogen chloride, sulfur dioxide, carbon dioxide, nitrogen dioxide, etc. when these gases are produced in the laboratory. However, it cannot be used to dry ethanol and ammonia, because ethanol and ammonia react with calcium chloride to form alcohol compound CaCl2·4C2H5OH and ammonia compound CaCl2·8NH3, respectively.