Calcium Chloride (CaCl₂)
Versatile inorganic compound used as a food additive, desiccant, road de-icer and in industrial applications
Overview
Calcium Chloride (CaCl₂, CAS No: 10043-52-4) is a highly hygroscopic inorganic salt appearing as white crystalline granules or pellets. It finds widespread use as a food additive (E509), road de-icer, desiccant and in various industrial applications.
Calcium chloride has very high water solubility (74.5 g/100 mL at 20°C) and releases significant heat when dissolved. Due to its hygroscopic nature, it absorbs moisture from the air and can become liquid over time. Its endothermic dissolution makes it effective as a de-icer.
Applications
Calcium Chloride has a wide range of industrial, commercial and food applications:
Food Additive (E509)
Used in cheese production, canned vegetables, jams and marmalades. Also serves as a calcium supplement in certain beverages.
De-Icer
Used as a de-icer on roads and sidewalks. More effective than salt (NaCl) and remains active down to -52°C.
Desiccant
Used for drying air and gases due to its high hygroscopic property, and in moisture control environments.
Concrete Additive
Used as a concrete accelerator. Speeds up setting time and prevents freezing at low temperatures.
Oil Industry
Used as a mud weighting agent in oil wells and in drilling fluids. Also acts as an antifreeze in pipelines.
Water Treatment
Used in water treatment plants as a hardness remover and flocculant. Effective in phosphate removal in wastewater treatment.
Technical Specifications
| Property | Value | Unit | Test Method |
|---|---|---|---|
| Chemical Name | Calcium Chloride | - | - |
| CAS Number | 10043-52-4 | - | - |
| EC No | 233-140-8 | - | - |
| Formula | CaCl₂ | - | - |
| Molecular Weight | 110.98 | g/mol | - |
| Appearance | White granules or pellets | - | Visual |
| Odor | Odorless | - | - |
| Purity | ≥94.0 | % | ISO 9001 |
| Moisture Content | ≤5.0 | % | Karl Fischer |
| pH Value (5% sol.) | 7.5-11.0 | - | ISO 1842 |
| Solubility (Water, 20°C) | 74.5 | g/100 mL | ISO 918 |
| Density | 2.15 | g/cm³ | ISO 787 |
| Melting Point | 772 | °C | ISO 6321 |
| Lead (Pb) Content | ≤5 | mg/kg | ISO 172 |
| Arsenic (As) Content | ≤3 | mg/kg | ISO 2590 |
Safety Information
Hazard Symbols and Statements
Irritant Corrosive Hygroscopic
Personal Protective Equipment (PPE)
- Chemical-resistant gloves (nitrile or neoprene)
- Protective goggles or face shield
- Dust mask (when working with powder)
- Lab coat or protective clothing
- Chemical-resistant shoes
Storage Conditions
- Store in a dry, well-ventilated place
- Keep in original packaging, tightly closed
- Protect from moisture and water (hygroscopic)
- Storage temperature: 15-25°C
- Store separately from acids and oxidizers
Fire Fighting
- Suitable extinguishers: Water spray, dry chemical powder, CO₂
- May release toxic hydrogen chloride gas at high temperatures
- Firefighting personnel must use full respiratory protection
- Use water spray or mist in large fires
Handling and Storage
Transportation
- Ensure containers are tightly closed
- Prevent moisture contact
- Do not transport with acids and oxidizers in the same vehicle
- Have absorbent material available for spills
- Use moisture-proof covers during transport
Storage
- Store in dry, cool and well-ventilated areas
- Display appropriate signage in storage area
- Protect from direct sunlight
- Store on elevated shelves
- Keep humidity low in storage area
Spill Response Measures
- Evacuate exposed personnel from area
- Use appropriate personal protective equipment
- Collect spill by dry method (sweeping)
- Avoid water contact (exothermic reaction)
- Wash spilled area with plenty of water
Regulatory Information
GHS Classification
- Skin Irritation/Corrosion Category 2
- Eye Irritation Category 1
- Acute Toxicity (Oral) Category 4
- Acute Toxicity (Dermal) Category 4
- Acute Toxicity (Inhalation) Category 4
Important Regulations
- REACH: Registered
- EPA: Listed in TSCA inventory
- European Food Additives Regulation: Approved as E509
- FDA: GRAS (Generally Recognized As Safe) status
- Food Codex: Permitted as food additive
Compliance Certificates
- ISO 9001:2015 Quality Management System
- ISO 22000:2018 Food Safety Management System
- GMP (Good Manufacturing Practices)
- Food grade certificate (for specific batches)
- HACCP certificate
Environmental Information
Environmental Impact
Calcium chloride can be harmful in aquatic environments at high concentrations. It may affect soil structure and plant growth. When used as road salt, it can damage vegetation and water sources. However, it is biodegradable and does not accumulate in nature.
Biodegradation
- Not biologically degradable, but does not accumulate in nature
- Water: Completely soluble and dissociates into ions
- Soil: May affect soil structure, increases salinity
- Air: Hygroscopic, absorbs moisture from air
Waste Management
- Not classified as hazardous waste
- For large quantities, comply with local regulations
- Dilute before discharging to sewer
- Consult wastewater treatment facilities
- Do not discharge directly to soil or water sources
Frequently Asked Questions
Why is calcium chloride used in foods?
Calcium chloride (E509) is used in foods for various purposes: 1) Promotes milk coagulation in cheese making, 2) Firms texture in canned vegetables, 3) Supports gelling in jams and marmalades, 4) Serves as a mineral supplement in some beverages. It also extends shelf life of foods.
Is calcium chloride a more effective de-icer than salt (NaCl)?
Yes, calcium chloride is more effective than salt (NaCl). It works down to -52°C, while salt loses effectiveness below -9°C. Less quantity is needed for the same effect. However, it is more expensive and can damage concrete surfaces more.
How should calcium chloride be stored?
Calcium chloride should be stored in a dry, cool and well-ventilated place. Protect from moisture and water as it is hygroscopic and can liquefy by absorbing atmospheric moisture. Keep in original packaging, tightly closed. Storage temperature should be 15-25°C. Do not store with acids or oxidizers.
What should I do if calcium chloride contacts skin?
If calcium chloride contacts skin, wash immediately with plenty of water and soap for at least 15 minutes. Seek medical attention if irritation persists. In case of eye contact, rinse eyes with plenty of water for at least 15 minutes and seek medical attention urgently. If inhaled, move to fresh air. If swallowed, rinse mouth with water, do not induce vomiting and seek immediate medical help.
What is the difference between calcium chloride dihydrate and anhydrous forms?
Anhydrous calcium chloride (94-97% purity) contains no water molecules, while dihydrate (CaCl₂·2H₂O) contains two water molecules. Anhydrous form has higher calcium chloride concentration and is more hygroscopic. Dihydrate form is more stable with lower moisture absorption tendency. Different forms are preferred depending on the application.