Europium Nitrate Hexahydrate, Europium Nitrate Hydrate, Europium Trinitrate Hexahydrate, 10031‑53‑5

Europium Nitrate Hexahydrate, Europium Nitrate Hydrate, Europium Trinitrate Hexahydrate, 10031‑53‑5

EUROPIUM(III) NITRATE HEXAHYDRATE 

Chemical Name: Europium(III) Nitrate Hexahydrate / Europium Trinitrate Hexahydrate
CAS Number: 10031-53-5
EC Number: 233-237-5
HS Code: 283429

1. PRODUCT IDENTIFICATION AND CHEMICAL IDENTITY

2. CHEMICAL STRUCTURE AND EXPLANATION

Chemical Structure and Bonding:

Europium(III) Nitrate Hexahydrate is an ionic compound composed of one Europium (Eu³⁺) cation and three Nitrate (NO₃⁻) anions. Europium is in the +3 oxidation state (trivalent) in this compound. The molecule contains six molecules of water of crystallization. The characteristic light pink color is due to the presence of Eu³⁺ ions, which have weak f-f electronic transitions in the visible region.

Molecular Formula Representation:

Eu(NO₃)₃·6H₂O

This formula indicates the following structure:

• 1 Europium ion (Eu³⁺): Central metal atom.

• 3 Nitrate groups (NO₃⁻): Trigonal planar anions.

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

Crystal Structure and Ionic Arrangement:

In the crystal structure, the Eu³⁺ ion is coordinated by oxygen atoms from nitrate groups and water molecules (typically 9-coordinate). Nitrate ions act as bridges between europium centers. The six 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:

        Eu³⁺   NO₃⁻   H₂O
          \     /       /
           Eu(NO₃)₃ · 6H₂O
          /     \       \
        NO₃⁻   NO₃⁻   H₂O

(An ionic crystal lattice composed of 1 Eu³⁺ ion, 3 NO₃⁻ ions, and 6 water molecules)

Structural Properties:

Dehydration (Loss of Water upon Heating):

Europium Nitrate Hexahydrate loses water sequentially when heated:

Eu(NO₃)₃·6H₂O → Eu(NO₃)₃·xH₂O → Eu(NO₃)₃ (anhydrous)

At higher temperatures, the nitrate groups decompose to form europium oxide (Eu₂O₃) and nitrogen oxides (NOx).

3. PHYSICAL AND CHEMICAL PROPERTIES

Important Physical Notes:

• Europium Nitrate Hexahydrate has a characteristic white to light pink color. The pink hue is due to the Eu³⁺ ion's f-f electronic transitions.

• It is highly hygroscopic and rapidly absorbs moisture from the air, requiring special packaging and storage conditions.

• It has a low melting point (~60°C); when heated, it dissolves in its own water of crystallization, forming a clear liquid.

• It has high solubility in water and ethanol, making it suitable for various applications.

• It exhibits oxidizing properties due to nitrate ions. Contact with organic materials should be avoided.

• High purity grades (≥ 99.9%) are available in rare earth element purity.

4. CHEMICAL PROPERTIES AND REACTIONS

Important Reactions:

1. Thermal Decomposition:

This reaction is the primary method used for producing europium oxide.

First, dehydration:
Eu(NO₃)₃·6H₂O → Eu(NO₃)₃ + 6H₂O (approximately 60-200°C)

Then, thermal decomposition:
4 Eu(NO₃)₃ → 2 Eu₂O₃ + 12 NO₂ + 3 O₂ (high temperature, >600°C)

2. Reaction with Bases (Precipitation):

Europium hydroxide precipitates, which can be used as an intermediate in europium oxide production.

Eu(NO₃)₃ + 3 NaOH → Eu(OH)₃ ↓ + 3 NaNO₃

3. Dissolution and Hydrolysis in Water:

Hydrolysis of europium ions causes the solution to become acidic.

Eu³⁺ + H₂O ⇌ Eu(OH)²⁺ + H⁺

4. Reduction to Eu²⁺:

Eu³⁺ can be reduced to Eu²⁺ using strong reducing agents:

Eu³⁺ + e⁻ → Eu²⁺ (E° ≈ -0.35 V)

This property is important in certain optical and magnetic applications.

5. Precipitation with Oxalate:

2 Eu(NO₃)₃ + 3 (NH₄)₂C₂O₄ → Eu₂(C₂O₄)₃ ↓ + 6 NH₄NO₃

5. APPLICATIONS AND INDUSTRIAL USES

5.1. Phosphors and Luminescent Materials (Most Important Application)

Europium compounds are critical in phosphor technology, particularly for red emission. Europium-doped phosphors are used in displays, lighting, and medical imaging. Europium Nitrate is a precursor for these phosphors.

5.2. Optical and Luminescent Materials

5.3. Catalyst Applications

5.4. Advanced Ceramics and Materials

5.5. Rare Earth Synthesis and Laboratory

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 materials.

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:

Europium(III) Nitrate Hexahydrate (Eu(NO₃)₃·6H₂O, CAS 10031-53-5) is an inorganic salt composed of one Europium (Eu³⁺) and three Nitrate (NO₃⁻) ions, containing six molecules of water of crystallization. It appears as a white to light pink crystalline solid, is highly soluble in water and ethanol, and is hygroscopic (moisture-absorbing). The light pink color is characteristic of Eu³⁺ ions.

Its most critical application is in phosphor technology, particularly for red-emitting phosphors used in displays (CRT, plasma, LED), fluorescent lamps, and scintillators. It is also used as a precursor for europium-based luminescent materials, catalysts, advanced ceramics, and as a laboratory reagent.

Under GHS classification, it is an oxidizer and harmful (H272, H302, H315, H319). Due to nitrate ions, it exhibits oxidizing properties and must be kept away from organic/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. Oxidizing Property: Exhibits oxidizing properties due to nitrate ions. Contact with organic materials, reducing agents, and combustible materials must be avoided. May intensify fire (H272). Therefore, it must be stored separately and away from combustible and reducing materials.

2. Hygroscopic Property and Moisture Sensitivity: Highly hygroscopic and rapidly absorbs moisture from the air. Storage and weighing operations must not be performed in humid environments. After opening, the container must be quickly resealed and storage under an inert atmosphere (nitrogen, argon) is preferred. Moisture absorption compromises weighing accuracy and stoichiometry. The pink color may fade or change if the compound absorbs significant moisture.

3. Low Melting Point and Thermal Instability: Melts at approximately 60°C by dissolving in its own water of crystallization. This is an important property to consider during thermal processes. At higher temperatures, nitrate groups decompose, releasing toxic nitrogen oxides (NO, NO₂). Thermal processes should be conducted in well-ventilated areas or under fume hoods.

4. Hydrated Structure and Stoichiometry: Contains six molecules of water of crystallization. Different hydration states have different molecular weights. The specific hydrate form must be confirmed when ordering and using the product. Stoichiometric calculations must account for the water content.

5. Structure and Purity: High purity (≥ 99.9%) is critical for phosphor, optical, and luminescent applications. Even trace amounts of other rare earth elements can quench the luminescence or shift the emission color. Purity specifications must be carefully verified for optical applications.

6. Color Stability and Optical Properties: The luminescent properties of europium compounds depend on the oxidation state (Eu³⁺ vs. Eu²⁺). Europium Nitrate contains Eu³⁺. Heating in a reducing atmosphere can convert it to Eu²⁺, which has different optical properties (blue emission). Care must be taken in processing to achieve the desired europium oxidation state.

7. 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.

8. 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.

9. Environmental Precautions: As a water-soluble salt, release into the environment (particularly water sources) must be prevented. Europium compounds may exhibit toxic effects in aquatic environments. Waste solutions must not be discharged into sewers and must be disposed of according to local regulations.

10. 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.

11. Special Warning for Phosphor Applications: The red emission from Eu³⁺ is due to the ⁵D₀ → ⁷F₂ transition. The efficiency of this emission depends on the local crystal field. Synthesis conditions (temperature, atmosphere, dopant concentration) must be carefully controlled to achieve optimal luminescent properties. Residual nitrate may affect phosphor performance and should be completely decomposed during synthesis.

12. Special Warning for Recycling and Waste: Europium is a critical raw material. Recovery and recycling of europium from waste phosphors and other materials should be considered to ensure sustainable supply and reduce environmental impact.

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 Europium(III) Nitrate Hexahydrate.