Lanthanum(III) Sulfate Hydrate: Properties & Lab Use FAQs

Lanthanum(III) Sulfate Hydrate is an inorganic rare-earth salt of lanthanum and sulfuric acid containing variable waters of crystallization, widely used as a research reagent in lanthanide chemistry, materials science, and biological studies.

Chemical Name

Lanthanum(III) Sulfate Hydrate

Molecular Formula

La2(SO4)3·nH2O

CAS Number (anhydrous basis)

10099-60-2

SKU

D304048

Appearance

White crystalline powder

Solubility

Soluble in water; exhibits inverse (retrograde) solubility — solubility decreases with increasing temperature

Element Group

Lanthanide (Rare Earth), Period 6

What Is Lanthanum(III) Sulfate Hydrate?

Lanthanum(III) Sulfate Hydrate is an inorganic salt with the general formula La₂(SO₄)₃·nH₂O, where n commonly equals 8 or 9. Lanthanum (La, atomic number 57) is the first element in the lanthanide series and is classified as a rare-earth metal. In this salt, lanthanum exists in its most stable +3 oxidation state, coordinated by sulfate anions and water molecules. The compound typically appears as a white, odorless crystalline powder. It is commercially produced by dissolving lanthanum oxide or lanthanum carbonate in dilute sulfuric acid followed by controlled crystallization. As a representative lanthanide salt, it serves as a versatile precursor and reagent across multiple scientific disciplines.

Key Physical and Chemical Properties

Lanthanum(III) Sulfate Hydrate possesses several notable physicochemical characteristics that researchers should understand before use:

• Appearance: White crystalline powder or granules.
• Solubility: Soluble in water. Importantly, it exhibits inverse (retrograde) solubility, meaning its aqueous solubility decreases as temperature increases — a relatively unusual property that must be considered when preparing solutions.
• Stability: Stable under normal laboratory conditions. The hydrate form may lose water of crystallization upon prolonged heating, converting toward the anhydrous salt.
• Reactivity: Non-flammable and non-explosive under standard conditions. Reacts with strong bases to precipitate lanthanum hydroxide. Compatible with most common laboratory solvents in its ionic, dissociated form in water.
• Hygroscopicity: Moderately hygroscopic; absorbs moisture from the air, which can alter the effective water content and should be accounted for in precise gravimetric preparations.

These properties make the compound reliable for aqueous solution preparation when temperature is carefully controlled.

Research Applications

Lanthanum(III) Sulfate Hydrate finds application across a broad range of research and industrial contexts:

• Materials Science and Synthesis: Used as a lanthanum source for the synthesis of lanthanum-doped phosphors, ceramics, perovskite-type oxides, and catalytic materials. Lanthanum doping can modify crystal structure, ionic conductivity, and optical properties.
• Catalysis: Lanthanum compounds are employed as promoters in heterogeneous catalysts, including those used in fluid catalytic cracking (FCC) and three-way automotive catalysts. Lanthanum sulfate can serve as a precursor in such catalyst preparations.
• Biological and Biomedical Research: La³⁺ ions competitively block calcium channels and have historically been used as an electron-dense tracer in electron microscopy to delineate extracellular spaces and membrane permeability studies.
• Analytical Chemistry: Used as a standard or interferent-masking agent in certain spectroscopic analyses (e.g., masking phosphate or sulfate interferences in flame atomic absorption spectrometry).
• Lanthanide Coordination Chemistry: Serves as a starting material for the synthesis of lanthanum coordination complexes, metal-organic frameworks (MOFs), and luminescent lanthanide assemblies.

Handling, Storage, and Safety Guidelines

While Lanthanum(III) Sulfate Hydrate is not classified as a highly hazardous substance under standard laboratory conditions, appropriate precautions should always be observed:

• Personal Protective Equipment (PPE): Wear appropriate laboratory gloves, safety glasses, and a lab coat when handling. If fine dust is generated, use a dust mask or work in a fume hood.
• Storage: Store in a tightly sealed container in a cool, dry, well-ventilated area away from strong bases and reducing agents. Because of its moderate hygroscopicity, desiccated storage is recommended to maintain product quality and accurate weighing.
• Disposal: Dispose of lanthanum-containing waste in accordance with local and institutional regulations for heavy metal or rare-earth waste streams. Do not pour concentrated solutions down the drain without proper treatment.
• First Aid: In case of skin or eye contact, rinse thoroughly with water. If ingested or inhaled in significant quantities, seek medical advice. Consult the Safety Data Sheet (SDS) for complete hazard information.

Always consult the current SDS provided by Aladdin Scientific before use.

Ordering and Specifications

Aladdin Scientific offers Lanthanum(III) Sulfate Hydrate under SKU D304048. When placing an order or evaluating this reagent, consider the following:

• Purity Grade: Confirm the purity grade (e.g., reagent grade, high-purity) appropriate for your application. Higher-purity grades are recommended for analytical, spectroscopic, or biological studies where trace-metal contamination could affect results.
• Quantity: Available in multiple package sizes to suit both small-scale research and larger preparative needs. Contact Aladdin Scientific for bulk pricing or custom specifications.
• Certificate of Analysis (CoA): A CoA documenting lot-specific purity and elemental analysis is available upon request. Verify the water content (hydration number) if stoichiometrically critical for your experiment.
• Lead Time and Shipping: Standard shipping conditions apply. As an inorganic salt, no special cold-chain requirements are typically needed, but confirm with your regional Aladdin Scientific representative.

For procurement inquiries, visit the Aladdin Scientific website or contact customer service directly.

Frequently asked questions

What is the water of crystallization in Lanthanum(III) Sulfate Hydrate, and does it affect my experiments?

Lanthanum(III) Sulfate Hydrate most commonly exists as the nonahydrate (La2(SO4)3·9H2O) or octahydrate form, though the precise hydration number can vary by lot and storage conditions. For stoichiometrically sensitive applications — such as preparing standard solutions of known molarity — it is important to verify the actual water content from the Certificate of Analysis (CoA) or by thermogravimetric analysis (TGA). For general preparative or qualitative work, the variability is usually not critical.

Why does lanthanum sulfate become less soluble in water as temperature increases?

Lanthanum sulfate is one of a relatively small class of inorganic salts that exhibit retrograde (inverse) solubility, meaning the dissolution process is exothermic overall. According to Le Chatelier's principle, increasing temperature shifts the equilibrium toward the endothermic direction — in this case, back toward the solid phase — thereby reducing solubility. Practically, this means solutions should be prepared at or near room temperature, and heating a lanthanum sulfate solution may cause precipitation.

Can Lanthanum(III) Sulfate Hydrate be used as a calcium channel blocker in cell biology experiments?

La3+ ions are well-established non-selective blockers of voltage-gated and other calcium channels due to the similar ionic radius of La3+ to Ca2+, combined with much higher charge density. Lanthanum(III) Sulfate Hydrate can serve as a source of La3+ ions for such studies; however, researchers should be aware that sulfate ions may themselves influence certain biological assays. In many cell biology protocols, lanthanum chloride (LaCl3) is preferred to avoid any confounding effects of sulfate. Always validate the chosen lanthanum salt for your specific biological system.

How should I store Lanthanum(III) Sulfate Hydrate to prevent degradation?

Store Lanthanum(III) Sulfate Hydrate in a tightly closed container placed in a cool, dry location away from moisture and incompatible materials such as strong bases. Because the compound is moderately hygroscopic, a desiccated environment (e.g., a desiccator with silica gel) is recommended for long-term storage. Avoid repeated opening of containers in humid conditions. Under proper storage, the material is stable for an extended period; refer to the product label or CoA for the stated shelf life.

Is Lanthanum(III) Sulfate Hydrate compatible with phosphate-buffered systems?

No — La3+ ions react with phosphate anions to form lanthanum phosphate (LaPO4), which is highly insoluble (Ksp extremely low). Mixing lanthanum sulfate solutions with phosphate-containing buffers such as PBS will result in immediate precipitation and is not recommended. If your experimental system requires phosphate buffers, use alternative buffers (e.g., HEPES, MOPS, or Tris) when working with lanthanum salts.

References

1. Cotton, S. Lanthanide and Actinide Chemistry. John Wiley & Sons, 2006. (General reference for lanthanide salt properties and chemistry.)
2. Greenwood, N.N.; Earnshaw, A. Chemistry of the Elements, 2nd ed. Butterworth-Heinemann, 1997. (Reference for retrograde solubility of lanthanum sulfate and general rare-earth chemistry.)
3. Van Breemen, C.; Farinas, J. Lanthanides and the study of Ca2+ transport. In: Calcium in Drug Actions. Springer, 1988. (Reference for La3+ as calcium channel blocker in biological studies.)
4. Aladdin Scientific Product Page. Lanthanum(III) Sulfate Hydrate, SKU D304048. (Product specifications and CoA source.)

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.