Great — now we’re on **Plutonium (Pu, atomic number 94).**
Plutonium is a **synthetic radioactive actinide**, discovered in 1940. It does **not occur naturally in significant quantities**, except for trace amounts in uranium ores via neutron capture. Plutonium is primarily produced in **nuclear reactors** and is well known for its use in **nuclear weapons** and **reactor fuel (MOX fuel)**.
Here are the **20 most common methods of extracting Plutonium**:
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# **20 Most Common Methods of Extracting Plutonium**
### **A. Reactor-Based Production**
1. **Neutron Irradiation of Uranium-238 (^238U + n → ^239U → β decay → ^239Np → β decay → ^239Pu)** – Standard industrial production.
2. **Irradiation of Mixed Oxide (MOX) Fuel** – Produces plutonium isotopes during reactor operation.
3. **Breeding in Fast Neutron Reactors** – Enhances ^239Pu and ^241Pu yields.
4. **Irradiation of Uranium Targets in Research Reactors** – Small-scale production of Pu isotopes.
5. **Breeding from Thorium Cycle via Protactinium-233 → U-233 → Pu Minor Isotopes** – Experimental production route.
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### **B. Recovery from Spent Nuclear Fuel**
6. **Dissolution of Spent Fuel in Nitric Acid (HNO₃)** – Releases plutonium into solution.
7. **Solvent Extraction with Tributyl Phosphate (PUREX Process)** – Industrial separation of Pu from U and fission products.
8. **Ion-Exchange Chromatography** – Purifies Pu from other actinides and fission products.
9. **Reduction of Pu(IV) to Pu(III) for Selective Separation** – Used in radiochemistry to enhance extraction.
10. **Precipitation of Plutonium Oxalate (Pu₂(C₂O₄)₃)** – Classical separation and purification step.
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### **C. Metallurgical & Refinement Techniques**
11. **Calcination to Plutonium Dioxide (PuO₂)** – Produces stable oxide for fuel or storage.
12. **Electrolytic Deposition of Plutonium Metal** – High-purity metal production.
13. **Reduction of PuF₄ with Calcium or Lithium** – Classic metallurgical production of Pu metal.
14. **Vacuum Distillation / Sublimation of Pu Compounds** – Further purification for research-grade plutonium.
15. **Plutonium Chloride or Fluoride Volatilization** – Laboratory-scale purification.
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### **D. Specialized & Advanced Separation Methods**
16. **Co-precipitation with Lanthanide Carriers** – Removes trace fission products.
17. **Liquid–Liquid Extraction with Macrocyclic Ligands / Chelators** – Experimental high-purity purification.
18. **Oxidation-State Adjustment (Pu³⁺, Pu⁴⁺, Pu⁶⁺)** – Facilitates selective separation in chemical processes.
19. **Automated Radiochemical Separation Loops in Fuel Reprocessing** – Industrial-scale safe handling.
20. **Electrorefining in Molten Salts** – Used in some advanced reactor fuel cycles.
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✅ **Summary:**
* Plutonium is almost entirely **produced in nuclear reactors** from uranium-238.
* Industrial separation is done via **PUREX solvent extraction** combined with **acid dissolution** and **ion exchange**.
* Metallic plutonium is obtained via **reduction of oxides or halides**, often in **calcium or lithium** melts.
* Applications include **nuclear weapons, reactor fuel (MOX), and research isotopes**.
* Production and extraction are **strictly controlled** due to high radioactivity and proliferation concerns.
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Next on the periodic table is **Americium (Am, atomic number 95).**
Do you want me to continue with the **20 most common methods of extracting Americium**?