Cerium Sulfate Tetrahydrate, Ceric Sulfate Tetrahydrate, Cerium Sulfate Hydrate, 10294‑42‑5

Cerium Sulfate Tetrahydrate, Ceric Sulfate Tetrahydrate, Cerium Sulfate Hydrate, 10294‑42‑5

CERIUM(IV) SULFATE TETRAHYDRATE 

Chemical Name: Cerium(IV) Sulfate Tetrahydrate / Ceric Sulfate Tetrahydrate
CAS Number: 10294-42-5
EC Number: 233-297-1
HS Code: 283429

1. PRODUCT IDENTIFICATION AND CHEMICAL IDENTITY

2. CHEMICAL STRUCTURE AND EXPLANATION

Chemical Structure and Bonding:

Cerium(IV) Sulfate Tetrahydrate is an ionic compound composed of one Cerium (Ce⁴⁺) cation and two Sulfate (SO₄²⁻) anions. Cerium is in the +4 oxidation state (tetravalent) in this compound. This is the highest oxidation state of cerium and imparts strong oxidizing properties to the compound. The molecule contains four molecules of water of crystallization (4H₂O).

Molecular Formula Representation:

Ce(SO₄)₂·4H₂O

This formula indicates the following structure:

• 1 Cerium ion (Ce⁴⁺): Central metal atom.

• 2 Sulfate groups (SO₄²⁻): Tetrahedral anions.

• 4 Water molecules (H₂O): Water of crystallization bound to the crystal lattice.

Crystal Structure and Ionic Arrangement:

In the crystal structure, the Ce⁴⁺ ion is coordinated by oxygen atoms (both from sulfate groups and water molecules). Sulfate ions and water molecules are arranged around the cerium center. The four water molecules are part of the crystal structure and impart specific thermal stability and solubility characteristics to the compound. Upon heating, these water molecules are sequentially removed (dehydration), eventually forming the anhydrous form.

Simplified Ionic Representation:

        Ce⁴⁺   SO₄²⁻   H₂O
          \     /       /
           Ce(SO₄)₂ · 4H₂O
          /     \       \
        SO₄²⁻  SO₄²⁻  H₂O

(An ionic crystal lattice composed of 1 Ce⁴⁺ ion, 2 SO₄²⁻ ions, and 4 water molecules)

Structural Properties:

Dehydration (Loss of Water upon Heating):

Cerium Sulfate Tetrahydrate loses water sequentially when heated:

Ce(SO₄)₂·4H₂O → Ce(SO₄)₂·xH₂O → Ce(SO₄)₂ (anhydrous)

The anhydrous form decomposes at higher temperatures to cerium oxide (CeO₂) and sulfur oxides.

3. PHYSICAL AND CHEMICAL PROPERTIES

Important Physical Notes:

• Cerium(IV) Sulfate Tetrahydrate is recognized by its characteristic yellow-orange color, which is due to the presence of the Ce⁴⁺ ion.

• Due to its hygroscopic nature, it absorbs moisture from the air, requiring special packaging and storage conditions.

• When dissolved in water, the solution becomes acidic due to the hydrolysis of Ce⁴⁺ ions.

• It is a strong oxidizing agent and reacts with organic and reducing substances.

• High purity grades (≥ 98%) are available in analytical reagent quality.

4. CHEMICAL PROPERTIES AND REACTIONS

Important Reactions:

1. Thermal Decomposition:

This reaction is used in the production of cerium oxide.

First, dehydration:
Ce(SO₄)₂·4H₂O → Ce(SO₄)₂ + 4H₂O (approximately 100-250°C)

Then, thermal decomposition:
Ce(SO₄)₂ → CeO₂ + 2 SO₃ (high temperature, >600°C)

2. Oxidizing Property (Cerimetry Titrations):

The Ce⁴⁺ ion is used as a strong oxidizer in analytical chemistry:

Ce⁴⁺ + e⁻ → Ce³⁺ (E° ≈ +1.44 V)

This property is utilized in cerimetry titrations (determination of iron, arsenite, oxalate, etc.).

3. Reaction with Reducing Agents:

Ce(SO₄)₂ + 2 FeSO₄ → Ce₂(SO₄)₃ + Fe₂(SO₄)₃

Oxidizes iron(II) ions to iron(III).

4. Reaction with Organic Substances:

Contact with organic substances causes oxidation reactions and may present fire and explosion hazards.

5. APPLICATIONS AND INDUSTRIAL USES

5.1. Analytical Chemistry (Most Important Application)

Cerium(IV) Sulfate Tetrahydrate is used as a standard oxidizing reagent in cerimetry titrations in analytical chemistry. This method is used for the determination of iron, arsenite, oxalate, hydrogen peroxide, and many other reducing substances.

5.2. Organic Synthesis

5.3. Catalyst and Precursor Material

5.4. Metal Surface Treatment

5.5. Electronics and Optical Materials

6. SECTORAL SUITABILITY TABLE

7. SAFETY AND TOXICOLOGY

Safety Precautions:

• Keep away from heat, sparks, and open flames.

• Store separately from combustible materials.

• Avoid dust formation.

• Work in well-ventilated areas.

• Use protective gloves, safety goggles, and dust mask.

• Wash hands thoroughly after handling.

• In case of eye contact, rinse with plenty of water for at least 15 minutes and seek medical attention.

• Avoid contact with organic substances at all times.

8. STORAGE AND HANDLING

9. TRANSPORT AND REGULATORY INFORMATION

10. QUALITY AND PURITY

11. RAW MATERIALS AND DOWNSTREAM PRODUCTS

11.1. Raw Materials (Upstream)

11.2. Downstream Products

12. FIRST AID MEASURES

13. FIREFIGHTING MEASURES

14. ACCIDENTAL RELEASE MEASURES

15. SUMMARY AND CRITICAL WARNINGS

SUMMARY:

Cerium(IV) Sulfate Tetrahydrate (Ce(SO₄)₂·4H₂O, CAS 10294-42-5) is an inorganic salt composed of one Cerium (Ce⁴⁺) and two Sulfate (SO₄²⁻) ions, containing four molecules of water of crystallization. It appears as a yellow-orange crystalline solid, is soluble in water, and is hygroscopic (moisture-absorbing). Upon heating, it first loses water of crystallization; at higher temperatures, it thermally decomposes to form cerium oxide (CeO₂) and sulfur oxides.

Its most critical application is as a standard oxidizing reagent in cerimetry titrations in analytical chemistry. It is also used as an oxidizing agent in organic synthesis, as a catalyst precursor in polymerization and fine chemical processes.

Under GHS classification, it is an oxidizer, harmful, and irritant (H272, H302, H315, H319). Due to its strong oxidizing properties, it must be kept away from organic and reducing substances. Due to its hygroscopic nature, it must be stored in a cool, dry environment in tightly closed packaging. Appropriate Personal Protective Equipment (PPE) must be used during handling to avoid inhalation of dust and contact with skin/eyes.

Key Properties:

CRITICAL WARNINGS:

1. Strong Oxidizing Property: Cerium(IV) Sulfate is a strong oxidizing agent. Contact with organic materials, reducing agents, and combustible materials must be strictly avoided. May intensify fire (H272). Therefore, it must be stored separately and away from combustible and reducing materials. Contact with organic solvents presents a fire and explosion risk.

2. Hydrated Structure and Thermal Instability: Contains four molecules of water of crystallization. Upon heating, it sequentially loses water (dehydration). It decomposes at approximately 250-300°C and at higher temperatures (>600°C) releases toxic sulfur oxides (SO₂, SO₃). Thermal processes should be conducted in well-ventilated areas or under fume hoods.

3. Hygroscopic Property: This is the most significant physical drawback. Storage and weighing operations must not be performed in humid environments. After opening, the container must be quickly resealed. Moisture absorption compromises weighing accuracy and chemical stoichiometry.

4. Color and Purity: The yellow-orange color indicates the presence of Ce⁴⁺ ions. Over time or due to moisture, Ce⁴⁺ ions may be reduced to Ce³⁺, resulting in color fading. This indicates product degradation. High purity (≥ 98%) and low Ce³⁺ content are critical for analytical applications.

5. Dust Control: The powder form can irritate the lungs if inhaled. Dust control measures must be implemented in the work area (closed systems, local exhaust ventilation) and appropriate respiratory protection (dust mask or N95/FFP2) must be used.

6. Aqueous Solution Acidity: Aqueous solutions are acidic due to hydrolysis. Appropriate protective equipment should be used when working with acidic solutions, and base solutions should be available for neutralization.

7. Environmental Precautions: As a water-soluble salt, release into the environment (particularly water sources) must be prevented. Waste solutions must not be discharged into sewers and must be disposed of according to local regulations.

8. Regulatory Compliance: Registration and notification requirements under REACH and KKDİK must be observed. It is classified as Class 5.1 (Oxidizing substance) under ADR/IMDG/IATA, requiring special labeling and documentation during transport. Use in food, cosmetics, and textile sectors is strictly prohibited.

9. Storage Warning: After opening the package, the remaining product should be immediately transferred to a moisture-proof container. It must be stored separately from combustible, reducing, and organic materials.

10. Cerimetry Applications: When preparing solutions for analytical titrations, it should be noted that Ce⁴⁺ solutions may degrade (be reduced) over time. Solutions should be prepared fresh or periodically standardized.

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(IV) Sulfate Tetrahydrate.