희토류 산화물의 염소화 및 열환원 공정을 통한 희토류 금속 및 합금 제조

목차 (Table of Contents)

• 1. Introduction 1
• 2. Theoretical Background 4
• 2.1. Production of Rare Earth Oxides 4
• 2.1.1. Mineral Processing 4
• 2.1.1.1. Comminution and Sieving 4
• 2.1.1.2. Flotation 5
• 2.1.1.3. Leaching 6
• 2.1.2. Solvent Extraction 8
• 2.2. Electrowinning Process 10
• 2.3. Chlorination 11
• 2.4. Metallothermic Reduction 12
• 3. Experimental 14
• 3.1. Materials 14
• 3.1.1. Composition of Rare Earth Oxides 14
• 3.1.2. Raw Material List by Process 17
• 3.2. Apparatus 18
• 3.2.1. Vacuum Drying Furnace 18
• 3.2.2. VAR (Vacuum Arc Remelting) 19
• 3.2.3. Horizontal Tube Furnace 20
• 3.2.4. Glove Box 21
• 3.3. Analysis 22
• 3.3.1. Calcination 22
• 3.3.2. Chlorination 22
• 3.3.3. Metallothermic Reduction 23
• 3.4. Procedure 24
• 3.4.1. Calcination Process 24
• 3.4.2. Chlorination Process 25
• 3.4.2.1. Manufacturing of NdCl 325
• 3.4.2.2. Manufacturing of TbCl3 and DyCl3 27
• 3.4.3. Metallothermic Reduction Process 28
• 3.4.3.1. Manufacturing of Nd and Nd-Fe alloys 28
• 3.4.3.2. Manufacturing of Tb-Fe and Dy-Fe alloys 33
• 4. Results and Discussion 34
• 4.1. Thermodynamic Considerations 34
• 4.1.1. Calcination 34
• 4.1.1.1. Neodymium oxide 34
• 4.1.1.2. Terbium oxide 35
• 4.1.1.3. Ammonium chloride 37
• 4.1.2. Chlorination 38
• 4.1.2.1. NdCl3 38
• 4.1.2.2. TbCl3 42
• 4.1.2.3. DyCl3 44
• 4.1.3. Metallothermic Reduction 46
• 4.1.3.1. Nd and Nd-Fe alloys 46
• 4.1.3.2. Tb-Fe and Dy-Fe alloys 53
• 4.2. Calcination Test 55
• 4.2.1. Nd2O 355
• 4.2.2. Tb2O3 57
• 4.2.3. Dy2O 360
• 4.3. Chlorination Test 61
• 4.3.1. NdCl 361
• 4.3.1.1. Manufacturing of NdCl3 powder using the horizontal tube furnace 61
• 4.3.1.2. Manufacturing of bulk NdCl3 using the horizontal tube furnace 67
• 4.3.1.3. Manufacturing of NdCl3 powder using the glove box 70
• 4.3.2. TbCl3 72
• 4.3.3. DyCl 374
• 4.4. Metallothermic Reduction Test 75
• 4.4.1. Nd and Nd-Fe alloys 75
• 4.4.1.1. Recovery rate of Nd 75
• 4.4.1.2. Micro-structure of Nd-Fe alloys 79
• 4.4.1.3. Salt analysis 83
• 4.4.2. Tb-Fe and Dy-Fe Alloys 86
• 5. Conclusion 87
• 5.1. Calcination 87
• 5.2. Chlorination 88
• 5.2.1. Manufacturing of NdCl3 88
• 5.2.2. Manufacturing of TbCl3 and DyCl 389
• 5.3. Metallothermic Reduction 90
• 5.3.1. Manufacturing of Nd and Nd-Fe alloys 90
• 5.3.2. Manufacturing of Tb-Fe and Dy-Fe alloys 91
• References 92