Excellent 👍 — next in order is **Phosphorus (P, atomic number 15).**
Phosphorus never occurs free in nature (too reactive). It’s bound in minerals like **apatite \[Ca₅(PO₄)₃(F,Cl,OH)]** and in organic matter. Historically, it was first isolated from **urine** in the 17th century. Today, most phosphorus is produced from **phosphate rock reduction in electric furnaces.**
Here are the **20 most common methods of extracting Phosphorus**:
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# **20 Most Common Methods of Extracting Phosphorus**
### **A. Industrial / Large-Scale Processes**
1. **Electric Arc Furnace Reduction of Phosphate Rock with Coke + Silica** – Main method today; yields elemental phosphorus vapor, later condensed (produces white phosphorus).
2. **Thermal Reduction of Apatite with Coke + Sand (Blast Furnace Type)** – Early industrial variant of the arc method.
3. **Electrothermal Process Using Phosphate Ore** – Large-scale process similar to arc reduction, but more controlled.
4. **Submerged-Arc Furnace Phosphorus Production** – Standard industrial setup.
5. **Carbothermic Reduction of Phosphoric Acid with Coke** – Produces P₄ and CO.
6. **Reduction of Calcium Phosphate with Silicon in Electric Furnace** – Used in some industrial plants.
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### **B. Historical Methods**
7. **Urine Distillation (Brand’s Method, 1669)** – The first discovery: heating large volumes of urine → phosphates → reduction → phosphorus.
8. **Bone Ash Reduction (18th–19th Century)** – Heating animal bones (calcium phosphate) with carbon and sand.
9. **Reduction of Sodium Phosphate with Charcoal** – Used in early chemistry labs.
10. **Reduction of Ammonium Phosphate Salts with Carbon** – Laboratory-scale production.
11. **Reduction of Phosphoric Acid with Charcoal in Clay Retorts** – 19th-century technique.
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### **C. Chemical Reduction Methods**
12. **Reduction of Calcium Phosphate with Aluminum Powder (Aluminothermic)** – Produces phosphorus + alumina.
13. **Reduction of Sodium Hexametaphosphate with Magnesium** – Lab-scale route.
14. **Reduction of Phosphates with Iron Silicide (Ferrosilicon)** – Variant of the electric furnace process.
15. **Reduction of Ammonium Phosphate with Hydrogen at High Temp** – Produces elemental phosphorus.
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### **D. Specialized / Modern / Research Approaches**
16. **Electrolysis of Molten Phosphates** – Research into producing phosphorus directly without carbon.
17. **Electrochemical Reduction of Phosphates in Ionic Liquids** – Experimental green method.
18. **Plasma Reduction of Phosphate Rock** – Uses plasma torches for energy efficiency.
19. **Biophosphate Recovery from Sewage / Wastewater** – Struvite (MgNH₄PO₄·6H₂O) recovery, then reduced to phosphorus.
20. **Solar-Thermal Carbothermic Reduction of Phosphates** – Uses concentrated solar energy to reduce phosphates into P₄.
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✅ **Summary:**
* **Today’s main method:** Electric arc furnace reduction of phosphate rock with silica + coke → elemental phosphorus (P₄).
* **Historic methods:** urine distillation, bone ash, phosphate reduction with carbon.
* **Research trends:** electrochemical extraction, plasma reduction, biophosphate recycling, solar carbothermic.
* **Forms produced:** Typically **white phosphorus (P₄)**, later converted to red or black phosphorus for safer use.
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Next in line is **Sulfur (S, atomic number 16).**
Would you like me to go ahead and list the **20 extraction methods for Sulfur**?