Cerium Chloride, Cerous Chloride, Cerium (III) Chloride, 18618-55-8

CERIUM CHLORIDE HEPTAHYDRATE (CERIUM(III) CHLORIDE) 

Chemical Name: Cerium(III) Chloride Heptahydrate / Cerium Chloride / Cerous Chloride
CAS Number: 18618-55-8
EC Number: 242-376-1
UN Number: 3077 (Environmentally hazardous substance)

1. PRODUCT IDENTIFICATION AND CHEMICAL IDENTITY

CHEMICAL STRUCTURE AND DESCRIPTION:

Cerium Chloride Heptahydrate (CeCl₃·7H₂O) is a hydrated salt of cerium in the +3 oxidation state. The compound crystallizes with seven molecules of water of hydration, forming a monoclinic crystal structure. The cerium ion (Ce³⁺) is coordinated by water molecules and chloride ions in the crystal lattice. This highly water-soluble salt is one of the most commonly used soluble cerium compounds in research and industrial applications.

Structural Features:

• Contains 7 water molecules of crystallization

• Highly hygroscopic; readily absorbs moisture from air

• Forms a monoclinic crystal system

• Readily dissolves in water and polar solvents

• Acts as a Lewis acid in organic synthesis

2. PHYSICAL AND CHEMICAL PROPERTIES

Cerium Chloride Heptahydrate is a white, odorless, highly water-soluble crystalline powder. It is strongly hygroscopic and must be stored under desiccated conditions. The melting behavior involves dissolution in its own water of crystallization at approximately 90°C. Aqueous solutions are weakly acidic due to hydrolysis. The salt is paramagnetic and exhibits typical rare earth ion properties.

3. SOLUBILITY PROFILE

Cerium Chloride Heptahydrate is highly soluble in water and polar solvents. Its aqueous solubility makes it an excellent precursor for various chemical processes. The solubility in alcohols allows for use in organic synthesis. The compound is insoluble in non-polar organic solvents.

4. CHEMICAL PROPERTIES AND REACTIONS

Cerium Chloride Heptahydrate is a typical rare earth salt with significant Lewis acid properties. In aqueous solution, it undergoes partial hydrolysis producing a weakly acidic pH. Upon heating, it loses its water of crystallization to form anhydrous cerium(III) chloride, which can further react with chlorine or oxygen. It readily forms complexes with various ligands and precipitates as hydroxide or oxalate with appropriate reagents.

Dehydration Reaction:
CeCl₃·7H₂O → CeCl₃ + 7H₂O (100-200°C)

Hydrolysis Reaction:
CeCl₃ + H₂O ⇌ Ce(OH)Cl₂ + HCl

5. SPECIFICATIONS (TECHNICAL AND HIGH PURITY)

Cerium Chloride Heptahydrate is available in various grades from technical (≥ 98%) to high purity (≥ 99.99%). High purity grades are essential for optical, electronic, and research applications where trace impurities significantly affect performance. Technical grades are suitable for metallurgical and general synthetic applications.

6. APPLICATIONS AND INDUSTRIAL USES

6.1. Organic Synthesis (Catalytic Applications)

Cerium Chloride Heptahydrate is a widely used mild Lewis acid catalyst in organic synthesis. It offers advantages over traditional Lewis acids such as aluminum chloride due to its water tolerance and mild reaction conditions.

6.2. Cerium Oxide (CeO₂) Production

Cerium Chloride is the most important soluble precursor for CeO₂ production via precipitation methods. The reaction with alkali or oxalate solutions yields cerium hydroxide or cerium oxalate, which upon calcination produces high-purity CeO₂.

CeO₂ Production Reaction:
CeCl₃ + 3NaOH → Ce(OH)₃ ↓ + 3NaCl
2Ce(OH)₃ + ½O₂ → 2CeO₂ + 3H₂O

6.3. Research and Laboratory Applications

6.4. Nanotechnology and Advanced Materials

6.5. Optical Glass and Ceramics

6.6. Defense and Specialized Optics

7. ALTERNATIVE / EQUIVALENT PRODUCTS

8. SECTOR SUITABILITY TABLE

9. COMMON NAMES

• Cerium salt

• White cerium crystals

• Cerium chloride powder

• Rare earth chloride

• Cerium trichloride

• Cerium(III) chloride

• Cerous chloride

10. PRODUCTION PROCESS

Reaction Equation:
Ce(OH)₃ + 3HCl → CeCl₃ + 3H₂O
(or using cerium carbonate or oxide)

Production Types: Technical and high purity grades

Major Producing Countries: China, India, United States, Russia, Japan

Commercial Purity: Ranges from 98% to 99.99%

11. SAFETY AND TOXICOLOGY

Cerium Chloride Heptahydrate is considered of low to moderate toxicity. The chloride ion is not considered highly toxic. However, as with all chemicals, appropriate handling procedures should be followed. It may cause irritation to skin, eyes, and respiratory tract. Chronic toxicity effects are not well documented. The compound is not classified as carcinogenic.

Special Warnings:

• Highly hygroscopic; avoid prolonged exposure to air

• Contact with strong oxidizing agents should be avoided

• Aqueous solutions are weakly acidic

• May react with strong bases releasing heat

12. TRANSPORT INFORMATION

Cerium Chloride is classified as an environmentally hazardous substance under UN 3077. Release into the environment must be prevented during transport. Proper packaging and labeling are required for international transport.

13. REGULATORY INFORMATION

Cerium Chloride Heptahydrate is registered in all major industrial markets. KKDİK registration is required for use in Turkey. It is classified under customs tariff code 2846.90.00.00.19. Proper import/export documentation is required for international trade.

14. STORAGE AND HANDLING

Handling Notes:

• CRITICAL: This compound is highly hygroscopic and must be handled in dry conditions

• Always use airtight containers after opening

• Weigh and transfer in a dry environment (glove box recommended)

• Avoid skin and eye contact (use protective gloves and safety goggles)

• Avoid dust formation and inhalation

• Do not store in metal containers if corrosion is a concern

• Keep away from strong oxidizers and bases

• Use under fume hood or with adequate ventilation

• Store away from direct sunlight

15. FIRE-FIGHTING MEASURES

Cerium Chloride Heptahydrate is not a flammable substance. In case of fire, protective clothing and SCBA must be used. Thermal decomposition may release corrosive hydrogen chloride and chlorine gases.

16. ACCIDENTAL RELEASE MEASURES

In case of spillage, appropriate personal protective equipment must be worn. Since the material is highly soluble, avoid addition of water to the spill. Clean up using dry methods. Environmental release must be prevented.

17. FIRST AID MEASURES

Special Notes:

• Cerium salts are considered of low acute toxicity

• Medical personnel should be informed about chloride salt exposure

• In case of ingestion, do not induce vomiting due to possible aspiration risk

18. RAW MATERIALS AND DOWNSTREAM PRODUCTS

18.1. Raw Materials (Upstream)

18.2. Downstream Products

19. QUALITY CONTROL PARAMETERS

20. SUMMARY AND CRITICAL WARNINGS

SUMMARY:

Cerium Chloride Heptahydrate (CeCl₃·7H₂O, CAS 18618-55-8) is a white to off-white, highly hygroscopic crystalline powder. It is the most common soluble form of cerium used in laboratory and industrial applications. The molecular weight is 372.58 g/mol (including seven waters of hydration), and it is highly soluble in water and alcohols. Aqueous solutions are weakly acidic (pH 4-5). The compound acts as a mild Lewis acid in organic synthesis and is a crucial precursor for the production of high-purity cerium oxide (CeO₂), nanoparticles, optical glasses, and other cerium-based materials.

Its most important applications include use as a Lewis acid catalyst in organic synthesis, a soluble precursor for CeO₂ nanoparticle production, and a reagent for rare earth analysis. It is also used in optical glass manufacturing to adjust refractive index, in ceramic pigmentation, and in research laboratories as a standard cerium source. Due to its high solubility, it is the preferred cerium salt for aqueous processing and precipitation reactions.

The compound is classified as an environmentally hazardous substance under UN 3077. While generally considered of low acute toxicity, it can cause skin, eye, and respiratory tract irritation. Its highly hygroscopic nature necessitates careful storage under dry conditions. Proper handling techniques using dry equipment and inert atmosphere are recommended. It should be stored in airtight containers away from moisture and strong oxidizers.

Key Properties:

Major Application Areas:

Key Safety Points:

• HAZARDOUS SUBSTANCE: UN 3077

• IRRITANT: Skin, eye and respiratory irritation

• HIGHLY HYGROSCOPIC: Must be stored in airtight containers

• CORROSIVE: Aqueous solutions are weakly acidic

• STORAGE: Cool, dry, airtight, under inert atmosphere if possible

• INCOMPATIBLE: Strong oxidizers, strong bases

• ECOTOXIC: Marine pollutant

• PROTECTIVE EQUIPMENT: Gloves, safety goggles, dust mask

CRITICAL WARNINGS:

1. HIGHLY HYGROSCOPIC: Cerium Chloride Heptahydrate absorbs moisture from the air rapidly. Containers must be opened only in dry environments and resealed immediately. Use under inert atmosphere (argon/nitrogen) for critical applications.

2. UN 3077 CLASSIFICATION: Classified as an environmentally hazardous substance. Release into the environment during transport, storage, or disposal must be strictly prevented. It is listed as a marine pollutant.

3. WATER SOLUBILITY: The extremely high water solubility makes it an excellent precursor for aqueous processing but also means that spillages must be contained to prevent environmental release.

4. LEWIS ACID PROPERTIES: As a mild Lewis acid, it requires appropriate handling in organic synthesis. Reaction with water can be exothermic; avoid adding water to concentrated solid.

5. PRECURSOR FOR CeO₂: This compound is the most important soluble precursor for cerium oxide production. The quality of the chloride salt directly affects the properties of the final CeO₂ product, including particle size, purity, and catalytic activity.

6. DEHYDRATION RISK: Upon heating, the compound loses its seven waters of crystallization, forming anhydrous cerium chloride. This process must be controlled carefully in applications requiring hydrated or anhydrous forms.

7. STORAGE SHELF LIFE: Under proper storage conditions (airtight, dry, cool), shelf life is 12-24 months. Improper storage leads to deliquescence and decomposition.

8. HANDLING IN DRY CONDITIONS: For moisture-sensitive applications, it is recommended to use a glove box or dry room. Weighing and transfer operations should be performed in low-humidity environments.

9. REACTION WITH BASES: Contact with strong bases produces cerium hydroxide precipitates with a significant exothermic effect. This is the basis for CeO₂ production but requires controlled conditions.

10. CUSTOMS CLASSIFICATION: The correct customs tariff code is 2846.90.00.00.19. Proper classification is essential for international trade, with potential country-specific restrictions for rare earth compounds.

Important Disclaimer: This Technical Data Sheet (TDS) is for informational purposes only. The information provided is based on available data and is believed to be accurate. However, the user is solely responsible for determining the suitability of the product for their specific applications and for complying with all applicable regulations and safety requirements. For complete safety, handling, storage, and regulatory compliance information, always refer to the official Safety Data Sheet (SDS/MSDS) provided by the manufacturer/supplier. Users are responsible for testing the product in their own processes and applications. All local, national, and international regulations must be followed when working with Cerium Chloride Heptahydrate. Due to its hygroscopic nature and environmental classification, a detailed risk assessment and handling procedure should be established prior to use.