Accumulation of rare earth elements on biogenic iron oxides: implication for the recovery of rare metals by biominerals

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K14172
• 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: Japan Agency for Marine-Earth Science and Technology
• Principal Investigator: Kikuchi Sakiko 国立研究開発法人海洋研究開発機構, 超先鋭研究開発部門(高知コア研究所), 研究員 (50758852)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 水酸化鉄 / 鉄酸化菌 / レアアース

Outline of Final Research Achievements

To understand adsorptive ability of biogenic iron oxyhydroxides (BIOS) to rare earth elements (REY), this study (i) measured the concentrations of REY in BIOS collected from various environmental conditions and (ii) characterized mineralogical properties of BIOS. We show that BIOS, especially those collected from groundwater discharge points, contained high concentrations of REY. BIOS had a negative surface charge at environmental pH, suggesting that the BIOS are electrostatically favorable for the accumulation of cationic REY.

Free Research Field

生物地球化学

Academic Significance and Societal Importance of the Research Achievements

バイオミネラルや微生物機能を活用した有用元素の回収は、既存の物理・化学プロセスと異なる省エネルギーかつ環境に優しいバイオテクノロジーとして注目されている。本研究から得られた天然におけるレアアースの濃集および濃集メカニズムを基に固相・液相を最適化することで、今後さまざまな水環境からレアアースを効率的・選択的に回収できる方法の提示につながると期待される。