Processing of Vietnamese lithium ores to produce LiCl Thesis submitted in partial fulfillment of the requirement of the degree Doctor rer. nat. of the Faculty of Environment and Natural Resources, Albert-Ludwigs-Universität Freiburg im Breisgau, Germany By Dinh, Thi Thu Hien Freiburg im Breisgau, Germany 2015 Name of Dean: Prof. Dr. Tim Freytag Name of Supervisor: Prof. Dr. Reto Gieré Name of 2nd Reviewer: Prof. Dr. Tam Tran Date of thesis' defence: 16.11.2015 Contents Acknowledgements .......................................................................................................... iv Abbreviations and symbols ............................................................................................... v List of Tables .................................................................................................................. vi List of Figures ................................................................................................................ viii Abstract .......................................................................................................................... xiii Kurzfassung ................................................................................................................... xiv Chapter 1. Introduction ..................................................................................................... 1 1.1. Background ........................................................................................................ 1 1.2. Objectives ........................................................................................................... 3 1.3. Dissertation structure ......................................................................................... 4 1.4. List of publications ............................................................................................. 5 Chapter 2. Literature Review ............................................................................................ 7 2.1. Use of lithium ..................................................................................................... 7 2.1.1. Ceramics and glass ...................................................................................... 8 2.1.2. Batteries ...................................................................................................... 8 2.1.3. Lubricating greases ..................................................................................... 9 2.1.4. Air treatment ............................................................................................... 9 2.1.5. Others .......................................................................................................... 9 2.2. Lithium processing technologies...................................................................... 10 2.2.1. Recovery lithium from brines ................................................................... 10 2.2.2. Recovery lithium from minerals ............................................................... 13 2.2.2.1. Lithium recovery from spodumene ................................................... 14 2.2.2.2. Recovery of lithium from lepidolite .................................................. 18 2.2.2.3. Recovery of lithium from zinnwaldite, petalite, and amblygonite .... 21 2.2.2.4. Recovery of lithium from clays and other ores ................................. 24 Chapter 3. Material and Analytical Procedures .............................................................. 26 3.1. Material ............................................................................................................ 26 3.2. X-ray diffraction (XRD) .................................................................................. 26 3.3. X-ray fluorescence (XRF) ................................................................................ 26 3.4. Thermal gravimetry (TG) ................................................................................. 27 i 3.5. Atomic absorption spectroscopy (AAS) .......................................................... 27 3.6. Electron probe microanalysis (EPMA) ............................................................ 27 3.7. Secondary ion mass spectrometry (SIMS) ....................................................... 28 3.8. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) ........................... 29 3.9. Ion Chromatography (IC) ................................................................................. 29 Chapter 4. Geological setting .......................................................................................... 30 Chapter 5. Bulk-Rock and Mineralogical Composition of the La Vi Ores .................... 35 5.1. Bulk-Rock Composition................................................................................... 35 5.2. Petrographic Features ....................................................................................... 39 Chapter 6. Experimental Procedures for Lithium Extraction ......................................... 45 6.1. Recovery of lithium-mica from ore .................................................................. 46 6.2. Roasting procedure ........................................................................................... 51 6.3. Leaching procedure .......................................................................................... 54 6.4. Purification procedure ...................................................................................... 54 6.5. Evaporation-Crystallization procedure ............................................................ 55 Chapter 7. Results and Discussion of Lithium Extraction Study ................................... 56 7.1. Mineral component of lepidolite concentrate .................................................. 56 7.2. Roasting of lepidolite to extract lithium ........................................................... 58 7.2.1. Effect of FeS/Li molar ratio ...................................................................... 58 7.2.2. Effect of roasting temperature and time ................................................... 60 7.2.3. Effect of Ca/F molar ratio ......................................................................... 63 7.2.4. Comparison of FeS with other additives................................................... 64 7.3. Leaching of lithium from calcines ................................................................... 68 7.3.1. Effect of water/calcine mass ratio ............................................................. 68 7.3.2. Effect of leaching temperature and time ................................................... 69 7.3.3. Comparison with other studies ................................................................. 70 7.4. Purification of leach liquor ............................................................................... 73 7.4.1. Removal of cations ................................................................................... 74 7.4.2. Removal of sulphate ................................................................................. 78 7.5. Recovery of LiCl .............................................................................................. 80 Chapter 8. Conclusions and Recommendations ............................................................. 85 8.1. Conclusions ...................................................................................................... 85 8.2. Recommendations ............................................................................................ 86 ii Appendix ......................................................................................................................... 99 Appendix 1: EMPA Results ...................................................................................... 100 Appendix 2: SIMS results ......................................................................................... 115 Appendix 3: Master size of flotation products .......................................................... 129 Appendix 4: 133XRD raw file of La Vi ores ............................................................ 133 Appendix 5: Technological experiments data .......................................................... 136 Appendix 6: Quality of Chemicals used ................................................................... 143 Appendix 7: Laboratory Equipment ......................................................................... 150 iii Acknowledgements I am greatly indebted to my supervisors Prof. Dr. Reto Gieré and Prof. Dr. Tam Tran for their guidance throughout the research and the writing of this dissertation. They were also able to help me overcome difficulties during my scientific experiments in my Ph.D.’s work and gave me opportunity to attend an international conference. In addition, I would like to thank PD. Dr. Eckardt Stein who has contributed significantly to make this dissertation possible. For my Ph.D. work, I appreciate the financial support of Prof. Dr. Reto Gieré, which made the scientific aspects of my research possible, and the Ministry of Education and Training of Vietnam (MOET) and German Academic Exchange Service (DAAD) for the 4-year scholarship. Furthermore, I would like to thank Mrs Sigrid Hirth-Walther, Mrs. Isolde Schmidt, Mr. Paul Robert Keppner, and Dr. Hiltrud Müller-Sigmund for their assistance during the laboratory and analytical work, and I also would like to thank to Mrs. Christine Höher, Mrs. Slavica Drndelic-Eich for providing a friendly atmosphere during the