Great — now we’re on **Radium (Ra, atomic number 88).**
Radium is an **alkaline earth metal**, discovered by **Marie and Pierre Curie** in 1898 while studying pitchblende (uraninite).
Unlike francium, radium is obtainable in **measurable quantities**, though it is still very rare and radioactive. It is found in **uranium and thorium ores** as a decay product. Historically, it was used in **luminous paint**, but due to health hazards, today it is used mainly in **research and medical isotopes**.
Here are the **20 most common methods of extracting Radium**:
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# **20 Most Common Methods of Extracting Radium**
### **A. From Uranium & Thorium Ores**
1. **Mining Pitchblende (Uraninite, UO₂)** – Primary natural source of radium.
2. **Processing Carnotite (K₂(UO₂)₂(VO₄)₂·3H₂O)** – Contains both uranium and radium.
3. **Processing Torbernite & Autunite** – Uranium-rich minerals with radium traces.
4. **Monazite Sand Extraction** – A thorium ore containing trace radium.
5. **Mining Pechblende Tailings** – Waste from uranium mines where radium concentrates.
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### **B. Chemical Separation**
6. **Sulfuric Acid Leaching** – Dissolves uranium/radium for separation.
7. **Hydrochloric Acid Digestion** – Used to dissolve radium-containing ores.
8. **Fractional Crystallization of Radium Chloride (RaCl₂)** – Curie’s original method to separate from barium.
9. **Precipitation as Radium Sulfate (RaSO₄)** – Radium sulfate is less soluble than barium sulfate.
10. **Precipitation as Radium Carbonate (RaCO₃)** – Selective precipitation step.
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### **C. Modern Refinement**
11. **Ion Exchange Chromatography** – Separates radium from chemically similar barium.
12. **Solvent Extraction Techniques** – Radium can be extracted using organic solvents.
13. **Liquid–Liquid Extraction with Crown Ethers** – Selective separation from barium and strontium.
14. **Extraction Using Chelating Agents (EDTA, DTPA)** – Radium forms stable complexes.
15. **Electrolytic Deposition of Radium Salts** – Used in purification.
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### **D. Recovery & Concentration**
16. **Recovery from Uranium Refining Waste** – Radium concentrates in tailings ponds.
17. **Recovery from Phosphate Rocks** – Trace radium present in phosphate deposits.
18. **Recovery from Old Luminous Paint Waste** – Secondary recovery method.
19. **Radium Extraction from Radon Emanation** – Tracing radium through its gaseous decay product (radon-222).
20. **Co-precipitation with Barium Carriers** – Barium salts used to help concentrate radium.
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✅ **Summary:**
* Radium is **much rarer than uranium** but can be concentrated from uranium ores.
* Historically, separation from barium was the biggest challenge (their chemistry is nearly identical).
* **Fractional crystallization of RaCl₂** and **precipitation as RaSO₄** were the Curie’s breakthrough methods.
* Today, radium is mainly extracted as a **byproduct of uranium mining**, then purified with modern ion-exchange and solvent extraction.
* Radium isotopes (especially ^223Ra and ^226Ra) are used in **cancer therapies** and **scientific research**, but handling requires extreme safety due to radioactivity.
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Next in line after radium is **Actinium (Ac, atomic number 89).**
Do you want me to continue with the **20 most common methods of extracting Actinium**?
