Development of an advanced magnetic separation technology assisted by agglomeration for improving the recovery of rare earth minerals from finely ground low-grade ores

• Project/Area Number: 20K15214
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 31020:Earth resource engineering, Energy sciences-related
• Research Institution: Hokkaido University
• Principal Investigator: PARK ILHWAN 北海道大学, 工学研究院, 助教 (80844753)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2022: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000); Fiscal Year 2021: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2020: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000)
• Keywords: 希土類元素 / 選鉱 / 磁力選別 / 凝集 / キャリア / Magnetic Separation / Rare Earth Minerals / Agglomeration

Outline of Research at the Start

REEs have been widely used in numerous high-tech applications. The bulk of currently operating RE mines are in China. Therefore, Japan should develop the way of recovering REE minerals to overcome the situation, which occur when China weaponize their REE exports.

Outline of Final Research Achievements

This research aimed at developing advanced magnetic separation techniques to improve the recovery of finely-ground rare earth-bearing minerals. Specifically, this research investigated two approaches: (i) agglomeration-magnetic separation and (ii) carrier-magnetic separation.
The conventional magnetic separation was inefficient in recovering finely-ground rare earth minerals (D50=2.9 μm) because magnetic force acting on a particle is directly proportional to its volume; that is, the finer the particle, the lower the magnetic force. The application of agglomeration process using emulsified kerosene prior to magnetic separation improved the recovery of rare earth mineral (i.e., bastnaesite-(Ce) (Ce(CO3)F))　from 50% to 94% due to the increase in particle size to > 8 μm. Moreover, the addition of magnetic particles like zero-valent iron as a carrier was effective in recovering fine bastnaesite.

Academic Significance and Societal Importance of the Research Achievements

カーボンニュートラルを達成するには希土類元素が重要な役割を担っているが、現在世界のレアアース鉱物供給量の約９割以上が４つの国（中国（70％）、米国（14％）、オーストラリア（6%）、ミャンマー（4%））に集中されているため、供給リスクが非常に高い。レアアースの供給リスクを低減するためには、これまで扱っていなかった低品位鉱石の開発が不可欠だ。本研究は、一般的な技術では回収できない微粉砕された希土類鉱物を回収するための新しいプロセスを開発することを目標とし、得られた結果は鉱山業界に大きく貢献すると考えられる。

Research Products

• [Journal Article] Beneficiation of Low-Grade Rare Earth Ore from Khalzan Buregtei Deposit (Mongolia) by Magnetic Separation (2021)
  • Author(s): Park Ilhwan、Kanazawa Yuki、Sato Naoya、Galtchandmani Purevdelger、Jha Manis Kumar、Tabelin Carlito Baltazar、Jeon Sanghee、Ito Mayumi、Hiroyoshi Naoki
  • Journal Title: Minerals Volume: 11 Issue: 12 Pages: 1432-1432
  • DOI: 10.3390/min11121432
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Recovery of Rare Earth Metals (REMs) from Nickel Metal Hydride Batteries of Electric Vehicles (2021)
  • Author(s): Jha Manis、Choubey Pankaj、Dinkar Om、Panda Rekha、Jyothi Rajesh、Yoo Kyoungkeun、Park Ilhwan
  • Journal Title: Minerals Volume: 12 Issue: 1 Pages: 34-34
  • DOI: 10.3390/min12010034
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Development of Hydrometallurgical Process for Recovery of Rare Earth Metals (Nd, Pr, and Dy) from Nd-Fe-B Magnets (2021)
  • Author(s): Choubey Pankaj Kumar、Singh Nityanand、Panda Rekha、Jyothi Rajesh Kumar、Yoo Kyoungkeun、Park Ilhwan、Jha Manis Kumar
  • Journal Title: Metals Volume: 11 Issue: 12 Pages: 1987-1987
  • DOI: 10.3390/met11121987
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Copper and critical metals production from porphyry ores and E-wastes: A review of resource availability, processing/recycling challenges, socio-environmental aspects, and sustainability issues (2021)
  • Author(s): C.B. Tabelin, I. Park, T. Phengsaart, S. Jeon, M. Villacorte-Tabelin, D. Alonzo, K. Yoo, M. Ito, N. Hiroyoshi
  • Journal Title: Resources, Conservation & Recycling Volume: - Pages: 105610-105610
  • DOI: 10.1016/j.resconrec.2021.105610
  • Peer Reviewed / Int'l Joint Research
• [Presentation] 高勾配湿式磁選における微粉砕レアアース鉱物の回収率向上のための油滴造粒の応用 (2021)
  • Author(s): 金沢 優輝、伊藤 真由美、佐藤 尚也、Sanghee Jeon、Park Ilhwan、広吉 直樹
  • Organizer: 資源・素材学会(2021年度秋季大会)
• [Presentation] Enhanced magnetic separation of finely-ground rare earth minerals by oil agglomeration (2021)
  • Author(s): Yuki Kanazawa, Mayumi Ito, Naoya Sato, Sanghee Jeon, Ilhwan Park and Naoki Hiroyoshi
  • Organizer: International Symposium on Earth Science and Technology 2021
  • Int'l Joint Research
• [Presentation] モンゴル・Khalzan Burgedei産レアアース鉱石の高勾配湿式磁選～各種運転条件の影響～ (2020)
  • Author(s): 伊藤 真由美、金沢 優輝、佐藤 尚也、Jeon Sanghee、Park Ilhwan、広吉 直樹
  • Organizer: 資源・素材学会(2020年度秋季大会)