Introduction
Calcium chloride (CaCl2) is one of the most versatile industrial chemicals on the planet. A simple salt of calcium and chlorine, it shows up in places you would never guess — keeping winter roads safe, suppressing dust on mining haul roads, finishing oil and gas wells, drying the air inside shipping containers, and even keeping the cheese on your pizza smooth and melty. For procurement teams, plant managers, and distributors, calcium chloride is a high-volume, mission-critical input. Getting the grade, form, spec, packaging, and supplier right has a direct impact on cost, safety, and operational uptime.
This guide is written for international buyers — importers, distributors, and industrial end users — who need a practical, accurate reference. It explains what calcium chloride is, how it behaves, the commercial grades and physical forms available, the major applications, the specifications that matter, packaging and logistics, safety and compliance, and a sourcing checklist you can use to evaluate suppliers. Whether you are comparing calcium chloride flakes vs pellets, trying to understand 94% min vs 77% min, or evaluating a new factory in China, this guide gives you a working framework.
1. What Is Calcium Chloride?
Calcium chloride is an inorganic salt with the chemical formula CaCl2. At room temperature it is a white, crystalline, odorless solid that is highly soluble in water and extremely hygroscopic — meaning it actively pulls moisture out of the surrounding air. Two properties drive almost every commercial use of calcium chloride:
- Strong moisture absorption (deliquescence). CaCl2 can absorb several times its own weight in water and will eventually dissolve in the moisture it captures. This is why it is the workhorse desiccant for dehumidification and road dust control.
- High exothermic heat of solution. When CaCl2 dissolves in water it releases a large amount of heat (about −83 kJ/mol). Combined with its ability to depress the freezing point of water down to about −51 °C, this makes it an outstanding de-icing and freezing-point depressant.
Calcium chloride also has useful secondary properties: it raises the calcium hardness of water (important in pools, drilling fluids, and concrete), acts as an electrolyte, and functions as a multi-purpose food additive approved under the codeword E509.
Key facts at a glance
| Property | Value |
|---|---|
| Chemical formula | CaCl2 |
| Molar mass | 110.98 g/mol |
| Appearance | White solid (flakes, pellets, powder, briquettes, liquid) |
| Solubility in water (20 °C) | ~74.5 g / 100 mL |
| Melting point | 772 °C (anhydrous) |
| Freezing-point depression of water | Down to about −51 °C at the eutectic |
| pH (aqueous solution) | Neutral to slightly alkaline |
| Common CAS number | 10043-52-4 |
E-E-A-T note: Values above are standard reference figures. Always validate against the Certificate of Analysis (COA) supplied with each shipment and the manufacturer’s Technical Data Sheet (TDS).
2. Calcium Chloride Grades: Anhydrous, Dihydrate, Food, and Industrial
Commercial calcium chloride is sold by purity and by hydration state. Knowing the difference prevents expensive mistakes.
- Anhydrous calcium chloride (CaCl2). Minimum 94% CaCl2. Essentially water-free. Used as a drying agent, in laboratory and chemical synthesis work, and where maximum active content per kilogram is required.
- Dihydrate calcium chloride (CaCl2·2H₂O). Typically 74–77% CaCl2. The dihydrate contains two water molecules per formula unit. Lower active content than anhydrous but easier to handle and less prone to caking.
- Industrial grade. 77% min or 94% min CaCl2. The most common grades for de-icing, dust control, oilfield, and construction. Specifications typically allow higher tolerances for magnesium and alkali salts.
- Food grade (E509). Manufactured under food-safety management systems (HACCP, FSSC 22000, ISO 22000) and meeting the specifications of the current Food Chemicals Codex (FCC), EU food additive regulation, and/or USP/FCC. Strict limits on heavy metals (lead, arsenic, mercury), fluoride, and microbial purity.
Typical specification — 77% min flake (industrial)
| Parameter | Specification |
|---|---|
| Appearance | White flake |
| CaCl2 content | ≥ 77% |
| Alkaline salts (as Ca(OH)₂) | ≤ 0.35% |
| Total magnesium (as MgCl2) | ≤ 0.1% |
| Water-insoluble matter | ≤ 0.1% |
| Sulfate (as SO₄²⁻) | ≤ 0.1% |
| Fe | ≤ 0.002% |
| pH (aqueous solution) | 7.5–11.0 |
Typical specification — 94% min flake (industrial)
| Parameter | Specification |
|---|---|
| Appearance | White flake |
| CaCl2 content | ≥ 94% |
| Total magnesium (as MgCl2) | ≤ 0.2% |
| Alkaline salts (as Ca(OH)₂) | ≤ 0.35% |
| Water-insoluble matter | ≤ 0.15% |
| Sulfate (as SO₄²⁻) | ≤ 0.15% |
| Fe | ≤ 0.003% |
Buyer tip: Always request the COA for the specific lot being shipped, not a generic specification sheet. Lot-to-lot variation in magnesium and insolubles is the most common cause of disputes.
3. Physical Forms: Flakes, Pellets, Powder, Briquettes, Liquid
Calcium chloride is sold in several physical forms. The right choice depends on the application, the equipment that will apply it, and the speed of dissolution you need.
Calcium chloride flakes
Flat, thin, irregular flakes. The most economical form for bulk applications. Easy to spread with conventional equipment. Dissolve quickly due to high surface area. Dominant form for road de-icing, dust control, and oilfield fluids.
Calcium chloride pellets
Spherical or rounded prills, usually 1–4 mm. Dense, low-dust, free-flowing. Preferred for consumer-pack de-icers (because they look clean and don’t track), refrigeration brines, and any system where controlled dissolution and minimal caking matter.
Calcium chloride powder / prills
Fine material used where rapid dissolution is required or as an input to formulated products (drilling mud additives, food-grade solutions, pharmaceutical intermediates).
Calcium chloride briquettes / mini-pearls
Larger compressed pieces used in gas drying towers and some desiccant applications where slow, controlled moisture uptake and structural integrity are needed.
Calcium chloride liquid (brine)
Aqueous solutions, typically 32%, 35%, or 38% CaCl2, sold in bulk tanker, IBC tote, or drum. Used directly for road pre-wetting and anti-icing, dust control, refrigeration brines, and oilfield fluids. Buying liquid avoids on-site dissolution but raises freight cost per unit of active CaCl2.
4. Major Industrial Applications of Calcium Chloride
4.1 De-icing and anti-icing of roads
Calcium chloride is the most effective common de-icer at low temperatures. While rock salt (sodium chloride) loses effectiveness below about −9 °C (15 °F), calcium chloride brine continues melting ice down to about −32 °C (−25 °F) in practical use, with the eutectic at roughly −51 °C. Because it is hygroscopic and exothermic, it bonds to pavement and resists being washed or blown away. Common strategies:
- Pre-wetted salt. Rock salt sprayed with CaCl2 brine to accelerate melting and reduce bounce.
- Direct liquid anti-icing. Brine applied before a storm to prevent ice bonding to the road.
- Blended de-icers. CaCl2 combined with NaCl, MgCl2, or agricultural by-products.
4.2 Dust control and road stabilization
On unpaved haul roads, construction sites, mine roads, and gravel airstrips, calcium chloride pulls moisture from the air and holds it in the road surface, suppressing dust and stabilizing the base. Benefits include lower equipment maintenance, improved visibility and safety, and reduced aggregate loss. A single treatment can remain effective for weeks under moderate traffic.
4.3 Oil and gas drilling and completion
In the oilfield, calcium chloride is used to weight and stabilize drilling fluids, prepare clear brine completion and workover fluids, and as a cement additive. Typical brine densities range from 1.2 to 1.4 SG (10–11.6 lb/gal). Calcium chloride brines are valued for clarity, compatibility, and cost relative to heavier (and much more expensive) fluids like calcium bromide or zinc bromide.
4.4 Concrete acceleration and construction
Added to ready-mix concrete in cold weather, calcium chloride accelerates setting and early strength gain, allowing pours at lower temperatures and faster formwork turnaround. Typical dosage is 1–2% by weight of cement. (Note: chloride accelerators are not suitable for reinforced or pre-stressed concrete because of corrosion risk — sulfate-based alternatives are used there.)
4.5 Desiccation and moisture control
Anhydrous calcium chloride is used as a desiccant in packaging, shipping containers (to stop “container rain”), and gas-drying systems. Container desiccants based on CaCl2 can absorb 100–200% of their own weight and protect cargo like machinery, electronics, textiles, and agricultural products from mold, corrosion, and label peel.
4.6 Food and beverage (E509)
Food-grade calcium chloride (E509) is used as a firming agent (canned vegetables, pickles), electrolyte in sports drinks, mineral source in brewing water adjustment, cheese manufacture (curd formation), and to improve the texture of fruit and vegetable processing. It must meet FCC/food-additive purity and be produced under an accredited food-safety system.
4.7 Other uses
- Tire ballast / weighting for tractors (improves traction).
- Water treatment — calcium hardness adjustment, fluoride removal aids, coagulation.
- Swimming pools — calcium hardness increaser to protect tile and equipment.
- Refrigeration brines — secondary coolant for ice rinks and cold-storage systems.
- Pharmaceutical and laboratory applications under GMP conditions.
- Latex coagulation in rubber glove manufacturing.
5. How to Choose the Right Grade and Form
Use this short decision framework before requesting quotations:
- What is the end use? Food/contact vs. industrial changes everything about the spec and documentation.
- What active content do you need? 77% vs 94% vs anhydrous — higher purity means less freight per unit of active CaCl2 but higher unit price.
- How will it be applied? Spreaders prefer flakes or pellets; tanks and brine systems prefer liquid; dry towers prefer briquettes.
- What is the storage environment? High humidity and long storage favor pellets over flakes (less caking) and require moisture-barrier packaging.
- What documentation do you need? COA, TDS, SDS, food-grade certificates (FCC, ISO 22000 / FSSC 22000), REACH registration, origin certificate, BL.
6. Packaging, Storage, and Logistics
Packaging options
- 25 kg / 50 lb multi-wall paper bags with PE liner — the global standard for dry product.
- 1000 kg / 2200 lb big bags (FIBCs / super sacks) — lower handling cost for bulk users.
- PE drums or pails — for premium consumer and food-grade product.
- Jumbo lined containers — bulk shipment for very large-volume buyers.
- Liquid: IBC totes (1000 L), drums (200 L), ISO tanks, and bulk tankers.
Storage
Because calcium chloride is strongly hygroscopic, moisture control is everything:
- Store in a dry, covered, well-ventilated warehouse.
- Keep bags on pallets, off the floor, away from doors and leaks.
- Reseal opened packages immediately.
- Avoid long storage near humidity-sensitive goods; CaCl2 will pull moisture that can damage neighbors.
- Stack height should respect bag and pallet integrity.
Logistics
Calcium chloride is classified as a non-dangerous good for transport in most jurisdictions (no UN number for solid CaCl2), which simplifies shipping compared with other chlorides. However:
- Concentrated liquid solutions can be regulated; confirm with your freight forwarder.
- Packaging and labeling must still meet the destination country’s chemical labeling rules (e.g., GHS/CLP in the EU, OSHA HazCom in the US).
- Confirm HS code (commonly 2827.20 for calcium chloride) for import duties and preferential tariffs.
7. Safety, Handling, and Compliance
Calcium chloride is a low-toxicity chemical, but it is not harmless. Treat it with standard industrial chemical hygiene.
- Skin and eye contact: Dust and concentrated solutions can irritate skin and eyes; use gloves and goggles. The heat of dissolution can cause burns with concentrated solutions.
- Ingestion: Low acute toxicity but unpleasant; do not ingest industrial grade.
- Inhalation: Dust may irritate the respiratory tract — use dust masks when handling dry product in bulk.
- Spills: Sweep up dry and reuse or dispose of in accordance with local regulations; avoid washing large amounts into storm drains (chloride and calcium load on water bodies).
- Corrosion: CaCl2 is chloride-bearing — protect steel, aluminum, and concrete rebar from prolonged contact, and rinse equipment.
- SDS: Always work from the supplier’s current Safety Data Sheet.
Regulatory touchpoints to confirm
- EU REACH registration status.
- US TSCA compliance.
- Food-grade certifications: FCC, ISO 22000 / FSSC 22000, BRC, Kosher/Halal if required.
- Country-specific chemical inventory listings (China IECSC, Japan METI, etc.).
- GHS classification and labeling for the destination market.
8. How to Evaluate a Calcium Chloride Supplier
A good supplier relationship reduces quality surprises, late shipments, and hidden costs. Use this checklist when shortlisting factories or trading partners:
- Production capability and capacity. Does the factory produce from its own raw material base, or only repackage? Capacity vs. your annual volume?
- Quality system. ISO 9001 at minimum; ISO 22000 / FSSC 22000 / HACCP for food grade; ISO 14001 for environmental.
- Consistent COAs. Request COAs from at least three recent shipments; look for variation in CaCl2 content, magnesium, and insolubles.
- Independent verification. Will the supplier accept third-party inspection (SGS, Intertek, BV) before shipment?
- Specification control. Can they hit custom specs (tighter Mg, lower Fe, specific particle size)?
- Packaging quality. Bag and liner integrity; ability to do private label.
- Logistics. Experience with your destination port; ability to provide FOB, CIF, or DDP; reliable forwarder.
- Responsiveness and English documentation. Clear, fast communication and complete export documents (COA, TDS, SDS, COO, BL, packing list, commercial invoice).
- References. Ability to provide buyer references or shipment records.
- After-sales support. How do they handle short-shipment, contamination, or spec-failure claims?
9. Common Questions From International Buyers (FAQ)
Is calcium chloride the same as rock salt?
No. Rock salt is sodium chloride (NaCl). Calcium chloride (CaCl2) melts ice at far lower temperatures, is hygroscopic, and is more expensive per ton. They are often used together.
Flakes or pellets — which should I buy?
For bulk road and industrial use, flakes are usually the most cost-effective. For packaged consumer de-icers, refrigeration, and applications sensitive to caking and dust, pellets are preferred.
Why does calcium chloride turn into liquid in storage?
Because it is deliquescent: at high relative humidity it absorbs water from the air until it dissolves. Keep it sealed and dry. This is normal chemistry, not a defect.
Can I use industrial-grade calcium chloride in food?
No. Only calcium chloride certified as food grade (E509, FCC), produced under a recognized food-safety system, may be used in food, beverage, or pharmaceutical applications.
How should I compare supplier prices?
Always compare on the basis of active CaCl2 per dollar delivered, not just cost per bag. A 94% flake may deliver more value per dollar than a 77% flake once freight and handling are included. Factor in moisture and insolubles.
Does calcium chloride damage concrete?
In undamaged, air-entrained concrete, properly applied CaCl2 de-icer is generally acceptable. It can contribute to scaling on low-strength or poorly cured concrete, and the chloride is corrosive to rebar — so it is not recommended for new or reinforced concrete. Follow manufacturer rates.
What is the shelf life?
Indefinite when stored sealed and dry. Practical shelf life is governed by packaging integrity and humidity exposure.
10. Conclusion
Calcium chloride is a deceptively simple product with a wide range of grades, forms, and uses. For international buyers, the keys to a successful purchase are: matching the grade and form to the application, validating the specification with lot-specific COAs, controlling moisture in storage and transit, and choosing a supplier whose quality system, documentation, and logistics match your operation.
Whether you are de-icing a northern highway network, suppressing dust on a 100 km mine haul road, finishing an offshore well, or sourcing E509 for a food plant, the framework in this guide will help you specify, evaluate, and buy with confidence.
Next steps
- Request a current COA and TDS for the exact grade you need.
- Define your annual volume, packaging, and Incoterm before contacting suppliers.
- Ask for third-party inspection on your first trial order.
- Use the sourcing checklist in Section 8 to compare at least three suppliers.
Need a calcium chloride quotation, a custom specification, or sample COAs for food-grade or industrial-grade material? contact our team for fast, documented pricing and full export paperwork.
Internal linking suggestions
- → *Calcium Chloride Flakes vs Pellets: Which Should You Buy?* (Article 2)
- → *Calcium Chloride vs Magnesium Chloride vs Sodium Chloride* (Article 3)
- → Product page: *77% Calcium Chloride Flake*
- → Product page: *94% Calcium Chloride Flake / Pellet*
- → Product page: *Food-Grade Calcium Chloride (E509)*
Recommended FAQ schema (FAQPage)
Use the seven FAQ entries in Section 9, each as a Question / Answer pair in JSON-LD, to earn rich-result eligibility in Google Search.