Calcium chloride

Calcium chloride (CAS 10043-52-4), also known by its food designation E509, is an inorganic salt sourced for its rapid moisture absorption and exothermic dissolution.

Where is Calcium chloride used?

• Road and pavement maintenance: dust suppressant and de-icing agent
• Oil and gas: dense brine solutions for wellbore stabilization and completion fluids
• Food manufacturing: firming agent in canned vegetables and tofu production
• Cheese coagulation processes maintain texture and quality.
• Concrete and construction: accelerates cement hydration to shorten setting times in cold-weather pours
• Refrigeration systems: component of brine.
• Wastewater treatment: regulates hardness and improves solids removal.
• Oil and gas: increases the density of drilling fluids and reduces scale formation in pipes and equipment.
• Brines: provides a salty taste without adding sodium.

Good to know: Food and pharmaceutical grades meet stricter limits on heavy metals and impurities.

Formulation notes

• When preparing solutions, add calcium chloride slowly to water to control heat release; never add water directly to large amounts of dry material.
• Anhydrous calcium chloride must be stored separately from zinc.
• Lowest protection temperature of sodium chloride at the eutectic is -21°C at 23%.

Typical specification

• Deliquescence relative humidity is 45%, compared to 75% for sodium chloride.
• Calcium chloride hexahydrate melts at about 30 °C in its water of crystallization when heated.
• Heating above 200 °C completely releases water of crystallization and reforms anhydrous calcium chloride.

Regulatory status

• Regulated in the US as a food additive and GRAS substance under 21 CFR Parts 170-186, specifically sections 172.560, 178.1010 and 184.1193.

Storage, packaging and handling

• Attacks zinc in the presence of water, producing flammable/explosive hydrogen gas.
• Anhydrous calcium chloride is supplied as colourless or white odourless hygroscopic crystals.
• Must be stored in airtight containers.

Frequently asked questions about Calcium chloride

What happens when calcium chloride is heated to decomposition?

It decomposes on heating, releasing toxic and corrosive chlorine fumes.

Technical content is compiled and updated by the SoleChem product team from public technical sources; the certificate of analysis (COA) governs product-specific specifications.