Lutetium Nitrate Hydrate, Lutetium Nitrate, Lutetium Trinitrate Hydrate, 100641‑16‑5

Lutetium Nitrate Hydrate, Lutetium Nitrate, Lutetium Trinitrate Hydrate, 100641‑16‑5

LUTETIUM(III) NITRATE HYDRATE 

Chemical Name: Lutetium(III) Nitrate Hydrate / Lutetium Trinitrate Hydrate
CAS Number: 100641-16-5
EC Number: 600-057-6
HS Code: 283429

1. PRODUCT IDENTIFICATION AND CHEMICAL IDENTITY

2. CHEMICAL STRUCTURE AND EXPLANATION

Chemical Structure and Bonding:

Lutetium(III) Nitrate is an ionic compound composed of one Lutetium (Lu³⁺) cation and three Nitrate (NO₃⁻) anions. Lutetium is in the +3 oxidation state (trivalent) in this compound. The molecule contains a variable number of water molecules of crystallization (typically 6 molecules - hexahydrate). As the heaviest and densest rare earth element, lutetium has the smallest ionic radius among the lanthanides, giving it unique coordination chemistry properties.

Molecular Formula Representation:

Lu(NO₃)₃·6H₂O (hexahydrate form)

This formula indicates the following structure:

• 1 Lutetium ion (Lu³⁺): 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 Lu³⁺ ion is coordinated by oxygen atoms from nitrate groups and water molecules. Due to lutetium's small ionic radius (smallest among lanthanides), it typically exhibits lower coordination numbers (8-9) compared to larger lanthanides. Nitrate ions act as bridges between lutetium centers. The 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:

        Lu³⁺   NO₃⁻   H₂O
          \     /       /
           Lu(NO₃)₃ · xH₂O
          /     \       \
        NO₃⁻   NO₃⁻   H₂O

(An ionic crystal lattice composed of 1 Lu³⁺ ion, 3 NO₃⁻ ions, and x water molecules)

Structural Properties:

Dehydration (Loss of Water upon Heating):

Lutetium Nitrate Hydrate loses water sequentially when heated:

Lu(NO₃)₃·xH₂O → Lu(NO₃)₃·yH₂O → Lu(NO₃)₃ (anhydrous)

At higher temperatures, the nitrate groups decompose to form lutetium oxide (Lu₂O₃) and nitrogen oxides (NOx).

3. PHYSICAL AND CHEMICAL PROPERTIES

Important Physical Notes:

• Lutetium Nitrate appears as a white crystalline solid. Unlike many other lanthanide nitrates, it does not exhibit characteristic coloration due to the absence of f-electrons (Lu³⁺ has a filled 4f¹⁴ shell).

• 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.

• As the heaviest lanthanide, lutetium compounds have the highest density among rare earth elements.

4. CHEMICAL PROPERTIES AND REACTIONS

Important Reactions:

1. Thermal Decomposition:

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

First, dehydration:
Lu(NO₃)₃·xH₂O → Lu(NO₃)₃ + xH₂O (approximately 60-200°C)

Then, thermal decomposition:
4 Lu(NO₃)₃ → 2 Lu₂O₃ + 12 NO₂ + 3 O₂ (high temperature, >600°C)

2. Reaction with Bases (Precipitation):

Lutetium hydroxide precipitates, which can be used as an intermediate in lutetium oxide production.

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

3. Dissolution and Hydrolysis in Water:

Hydrolysis of lutetium ions causes the solution to become acidic.

Lu³⁺ + H₂O ⇌ Lu(OH)²⁺ + H⁺

4. Precipitation with Ammonia:

Lu(NO₃)₃ + 3 NH₃ + 3 H₂O → Lu(OH)₃ ↓ + 3 NH₄NO₃

5. Precipitation with Oxalate:

2 Lu(NO₃)₃ + 3 (NH₄)₂C₂O₄ → Lu₂(C₂O₄)₃ ↓ + 6 NH₄NO₃

5. APPLICATIONS AND INDUSTRIAL USES

5.1. Medical Imaging and Scintillators (Most Important Application)

Lutetium compounds, particularly Lutetium Oxyorthosilicate (LSO) and Lutetium-Yttrium Oxyorthosilicate (LYSO), are critical scintillator materials used in Positron Emission Tomography (PET) and other medical imaging applications. Lutetium Nitrate is a precursor for these scintillator materials.

5.2. Laser Crystals and Optics

5.3. Catalyst Applications

5.4. Advanced Ceramics and Materials

5.5. Rare Earth Synthesis and Laboratory

5.6. Electronics

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:

Lutetium(III) Nitrate Hydrate (Lu(NO₃)₃·xH₂O, CAS 100641-16-5) is an inorganic salt composed of one Lutetium (Lu³⁺) and three Nitrate (NO₃⁻) ions, containing a variable number of water molecules of crystallization (typically hexahydrate). It appears as a white crystalline solid, is highly soluble in water and ethanol, and is hygroscopic (moisture-absorbing). Unlike many other lanthanides, lutetium compounds are white due to the filled 4f¹⁴ electron configuration.

Its most critical application is as a precursor for LSO and LYSO scintillator crystals used in PET and other medical imaging applications. It is also used in laser crystals, optical materials, catalysts, and advanced ceramics. Lutetium is the heaviest rare earth element and has unique properties for high-density and high-performance applications.

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.

3. Variable Hydration State: The product may contain a variable number of water molecules of crystallization. Different hydrate forms have different molecular weights. The exact hydration state should be confirmed with the supplier. Stoichiometric calculations must account for the water content.

4. 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.

5. Structure and Purity: High purity (≥ 99.9%) is critical for scintillator, optical, and medical applications. Even trace amounts of other rare earth elements (particularly yttrium, ytterbium, thulium) can significantly affect scintillation properties or optical performance. Purity specifications must be carefully verified for critical applications.

6. Scintillator Application Requirements: For LSO and LYSO crystal production, extremely high purity is required. Even parts-per-million (ppm) levels of impurities can quench the scintillation light output. The nitrate precursor must be completely converted to oxide without residual nitrate, which can cause defects in the crystal.

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. Lutetium 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 Medical Imaging Applications: For PET scintillator production, the purity of lutetium nitrate is absolutely critical. Impurities such as cerium (which is often used as a dopant but must be controlled), iron, and other transition metals can significantly affect the light output and decay time of LSO/LYSO crystals. The nitrate-to-oxide conversion process must be carefully controlled to achieve high-quality crystals.

12. Special Warning for Laser Applications: For laser crystal applications, the purity and homogeneity of lutetium compounds are essential. Even small variations in composition or impurity levels can affect laser performance, efficiency, and thermal properties.

13. Critical Raw Material Status: Lutetium is one of the rarest and most expensive rare earth elements. Efficient use, recovery, and recycling of lutetium-containing materials from waste scintillators, lasers, and other sources should be considered to ensure sustainable supply. The nitrate form is particularly useful for solution-based processing and recovery methods.

14. Storage Warning: Due to the high cost and critical nature of lutetium compounds, special attention should be paid to proper storage and inventory management. Minimize exposure to air and moisture to prevent degradation and loss of product.

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 Lutetium(III) Nitrate Hydrate.