Perfect 👍 — next in **periodic table order** is **Samarium (Sm, atomic number 62).**
Samarium is a **lanthanide (rare earth metal)** that occurs primarily in **monazite (Ce,La,Sm,Th)PO₄** and **bastnäsite (Ce,La,Sm)(CO₃)F**. Industrial extraction involves **acid or alkaline digestion, solvent extraction, and reduction**.
Here are the **20 most common methods of extracting Samarium**:
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# **20 Most Common Methods of Extracting Samarium**
### **A. Extraction from Rare Earth Ores**
1. **Crushing and Grinding of Monazite or Bastnäsite** – Prepares ore for chemical treatment.
2. **Acid Digestion (H₂SO₄ or HCl) of Monazite** – Dissolves samarium and other REEs.
3. **Alkaline Digestion (NaOH) of Monazite** – Converts phosphate to soluble samarium salts.
4. **Leaching of Bastnäsite with Acid or Alkali** – Produces soluble samarium compounds.
5. **Purification by Precipitation of Thorium and Other Impurities** – Removes radioactive and heavy elements.
6. **Solvent Extraction of Samarium Salts** – Organophosphorus extractants separate Sm³⁺ from other REEs.
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### **B. Separation and Concentration**
7. **Ion Exchange Separation of Samarium** – Separates Sm³⁺ from lanthanum, cerium, praseodymium, and neodymium.
8. **Fractional Precipitation Using Oxalates or Hydroxides** – Concentrates samarium from mixed REE solutions.
9. **Conversion to Samarium Carbonate (Sm₂(CO₃)₃)** – Precursor for oxide formation.
10. **Calcination to Samarium Oxide (Sm₂O₃)** – Prepares for reduction or industrial use.
11. **Selective Solvent Extraction from Mixed REE Solutions** – Enhances separation efficiency.
12. **Chelating Agent Separation** – Laboratory or pilot-scale selective extraction.
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### **C. Reduction to Metallic Samarium**
13. **Calciothermic or Metallothermic Reduction of Sm₂O₃ → Sm** – Main industrial method.
14. **Electrolytic Reduction of Molten SmCl₃** – Produces high-purity metallic samarium.
15. **Vacuum Distillation of Metallic Samarium** – Purification for ultra-high purity Sm.
16. **Hydrogen Reduction of Samarium Halides** – Laboratory-scale method.
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### **D. Recovery from Byproducts / Secondary Sources**
17. **Recovery from Monazite Sands during Thorium Extraction** – Samarium collected as a byproduct.
18. **Recovery from Bastnäsite Refining** – Sm separated during cerium, lanthanum, praseodymium, or neodymium extraction.
19. **Recovery from Spent Rare Earth Catalysts** – Leaching + precipitation.
20. **Recovery from Recycled Electronics Containing REEs** – Hydrometallurgical extraction.
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✅ **Summary:**
* **Main industrial sources:** Monazite, bastnäsite.
* **Primary extraction steps:** Ore crushing → acid/alkaline digestion → purification → selective precipitation → reduction/electrolysis → metallic samarium.
* **Metallic samarium:** Produced via calciothermic/metallothermic reduction or molten salt electrolysis.
* **Byproduct sources:** Thorium extraction residues, bastnäsite processing, spent REE catalysts, recycled electronics.
* **Laboratory/experimental:** Ion exchange, selective solvent extraction, vacuum distillation, hydrogen reduction.
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Next in periodic order is \*\*Europium (Eu, atomic number 63).
Do you want me to continue with **20 extraction methods for Europium**?
