Extractive Metallurgy of Titanium. Conventional and Recent Advances in Extraction and Production of Titanium Metal

Table of Contents

Contents

Contributors xi

1. Introduction to the development of processes for primary

Ti metal production 1

Zhigang Zak Fang, Hyrum D. Lefler, F.H. Froes, and Ying Zhang

References 8

Part 1 Extractive chemical metallurgy processes 11

2. A brief introduction to production of titanium dioxide

and titanium tetrachloride 13

Michael L. Free

1. Background 13

2. Ore sources 13

3. Processing methods 14

References 17

3. Minerals, slags, and other feedstock for the production

of titanium metal 19

Dimitrios Filippou and Guillaume Hudon

1. Introduction 19

2. Ilmenite, rutile, and other natural titanium minerals 21

3. Ilmenite smelting to titania slag 26

4. Ilmenite conversion to synthetic rutile 32

5. Titania slag upgrading to UGS 36

6. Production of titanium carbide feedstock 37

7. Conclusions 38

Acknowledgments 41

References 41

4. Chemical processes for the production of titanium tetrachloride

as precursor of titanium metal 47

Guillaume Hudon and Dimitrios Filippou

1. Introduction 47

2. Titanium tetrachloride 47

3. Production of titanium tetrachloride 49

4. Titanium tetrachloride purification 55

5. Production of pure titanium dioxide 56

6. Other precursors 59

Acknowledgments 60

References 60

Part 2 Thermochemical reduction of TiCl4 63

5. Fundamentals of thermochemical reduction of TiCl4 65

Toru H. Okabe and Osamu Takeda

1. Historical developments in titanium metal production 65

2. Kroll process 66

3. Hunter process 71

4. Fundamentals of titanium reduction process 75

5. Electrochemical reactions during thermochemical reduction 78

6. Reduction mechanism of TiCl4 during the Kroll process 81

7. Past research for new titanium production processes 83

8. Summary 90

References 92

6. The Kroll process and production of titanium sponge 97

Matthew R. Earlam

1. Introduction 97

2. Source of ore 99

3. Production of TiCl4 100

4. Purification of TiCl4 101

5. The Hunter process 102

6. Armstrong process 103

7. Kroll process 103

8. Magnesium reduced acid leach (MRAL) (no longer practiced) 104

9. Vacuum distillation process TOHO timet 107

10. Preparation for melting 110

References 111

7. A modified Kroll process via production of TiH2 thermochemical

reductions of TiCl4 using hydrogen and Mg 113

Mykhailo Matviychuk, Andrey Klevtsov, and Vladimir S. Moxson

1. Introduction 113

2. Process description 114

3. Experimental results 120

4. Role of hydrogen for ADMA process 122

References 127

Further reading 128

Part 3 Thermochemical reduction of TiO2 129

8. Metallothermic reduction of TiO2 131

Toru H. Okabe

1. Introduction 131

2. Studies on reduction of titanium oxide before 2000 134

3. Studies on reduction of titanium oxide after 2000 143

4. Future prospects of metallothermic reduction processes for direct

production of titanium from oxides 155

5. Summary 159

References 160

9. Hydrogen assisted magnesiothermic reduction (HAMR) of

TiO2 to produce titanium metal powder 165

Yang Xia, Hyrum D. Lefler, Ying Zhang, Pei Sun, and Zhigang Zak Fang

1. Introduction 165

2. Fundamentals of the HAMR process 167

3. HAMR process description 172

4. HAMR product characterization 173

5. Summary 176

Acknowledgments 176

References 177

10. Deoxygenation of Ti metal 181

Ying Zhang, Zhigang Zak Fang, Pei Sun, Yang Xia, Hyrum D. Lefler,

and Shili Zheng

1. Introduction 181

2. Thermodynamic properties of the TieO solid solutions 182

3. Methods of deoxygenation 186

4. Concluding remarks 206

A. Appendix 207

Acknowledgments 220

References 220

Part 4 Electrochemical reduction of TiO2 and TiOC 225

11. Invention and fundamentals of the FFC Cambridge Process 227

George Z. Chen and Derek J. Fray

1. Background: how the concept of electro-deoxidation came about 227

2. Understanding of electro-deoxidation: interactions of the oxide cathode

with molten salts 230

3. Understanding of electro-deoxidation: metal/insulator/electrolyte 3PI

models 235

4. Understanding of electro-deoxidation: the metal-to-oxide molar volume

ratio 236

5. Development of an inert anode for electro-deoxidation in calcium

chloride based melts 241

6. Electro-deoxidation of other metal oxides 246

7. Electro-desulfidation of metal sulfides 257

8. Electro-deoxidation of mixed metal oxides 261

9. Titanium based medical implant materials 273

10. Cathodic protection of titanium 276

11. Outlook and Prospective 278

12. Conclusions 279

References 280

12. OS process: calciothermic reduction of TiO2 via CaO electrolysis

in molten CaCl2 287

Ryosuke O. Suzuki, Shungo Natsui, and Tatsuya Kikuchi

1. Introduction 287

2. Cell design 296

3. Thermodynamics of desired salt 298

4. Validity of Ca reduction during electrolysis 303

5. Conclusion 308

References 309

13. Titanium production through electrolysis of titanium oxycarbide

consumable anodedthe USTB process 315

Hongmin Zhu, Shuqiang Jiao, Jiusan Xiao, and Jun Zhu

1. Introduction 315

2. Crystalline structure of titanium oxycarbide and titanium

oxycarbonitride 316

3. Thermodynamic properties and preparation of titanium oxycarbide from

TiO2 by carbon thermal reduction 317

4. Electrochemical dissolution of consumable anode 320

5. Electrochemical deposition on the cathode 325

6. Scaling up and practices of USTB process 326

References 328

14. Electrolysis of carbothermic treated titanium oxides to produce

Ti metal 331

James C. Withers

References 343

Further reading 347

Part 5 Other processes 349

15. Selected processes for Ti production e a cursory review 351

Pei Sun, Ying Zhang, and Zhigang Zak Fang

1. Introduction 351

2. Continuous processes using Mg or Na as the reductant 352

3. Processes using low-cost alternatives as reductants 356

4. Summary 360

Acknowledgments 360

References 360

16. Recycling of Ti 363

Osamu Takeda, Toru H. Okabe

1. Introduction 363

2. Ti scraps generated in the smelting process 364

3. Ti scraps generated in the aircraft industry 367

4. Material flow of Ti scraps 373

5. Recycling technologies for Ti scraps 374

6. Future perspective of recycling technologies 377

7. Conclusions and future remarks 382

Acknowledgments 383

References 383

17. Energy consumption of the Kroll and HAMR processes for

titanium production 389

Yang Xia, Hyrum D. Lefler, Zhigang Zak Fang, Ying Zhang, and Pei Sun

1. Introduction 389

2. Review of energy consumption in the Kroll process 390

3. Modeling and analysis of energy consumption in the HAMR process 398

4. Energy consumption in other emerging processes 404

5. Summary and comparison of Kroll and HAMR processes 405

Acknowledgments 406

References 407

Index 411

Authors

Zhigang Zak Fang University of Utah, USA. Dr Zhigang Zak Fang is a Professor in the Powder Metallurgy Research Laboratory of the Faculty of Metallurgical Engineering at the University of Utah, USA. Francis Froes Department Chair, Materials Science and Engineering, University of Idaho (retired), Director, Institute for Materials and Advanced Processes (IMAP) (retired). Francis H Froes, Ph.D. has been involved in the Titanium field with an emphasis on Powder Metallurgy (P/M) for more than 40 years. He was employed by a primary Titanium producer-Crucible Steel Company-where he was leader of the Titanium group. He was the program manager on a multi-million dollar US Air Force (USAF) contract on Titanium P/M. He then spent time at the USAF Materials Lab where he was supervisor of the Light Metals group (which included Titanium). This was followed by 17 years at the University of Idaho where he was a Director and Department Head of the Materials Science and Engineering Department. He has over 800 publications, in excess of 60 patents, and has edited almost 30 books-the majority on various aspects of Titanium again with an emphasis on P/M. He gave the key-note presentation at the first TDA (ITA) Conference. In recent years he has co-sponsored four TMS Symposia on Cost Effective Titanium featuring numerous papers on P/M. He is a Fellow of ASM, is a member of the Russian Academy of Science, and was awarded the Service to Powder Metallurgy by the Metal Powder Association. Recently he has been a co-author of three comprehensive papers on the Additive Manufacturing of Titanium. Ying Zhang Associate Professor, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China. Dr. Ying Zhang is an associate professor in the Institute of Process Engineering, Chinese Academy of Sciences (IPE, CAS), who joined the faculty in 2011 after the graduation. She graduated from Central South University of China with BS degree in 2006, and received her Ph.D degree from the University of Chinese Academy of Sciences in 2011 in the research field of metallurgy. From February 2014 to November 2016, Dr. Zhang joined Prof. Zak Fang's research group in the University of Utah as a Post-doctor, working on the project of titanium metal powder production under the financial support from the DOE of US. Prior to that, Dr. Zhang was in charge of and participated in a few projects supported by either the Chinese government or industries, including NSFC, the Ministry of Science and Technology of China, Hunan Provincial Science & Technology Department, etc., focusing on the cleaner production of nonferrous metals (including Al, Cr, Zn and Cd). Now she continues her interests in the production of titanium-group metals under the financial support from NSFC as PI. Dr. Zhang has authored/co-authored over 30 publications and over 20 patents.