Mineral Dynamics Revealed by Fe 2+ -Catalyzed Recrystallization of U-Incorporated Goethite

作者：Qingyin Xia, Prachi Joshi, Zezhen Pan, Marina Lazarov, Barbora Bártová, Xiyang Xu, T. Prüßmann, Andreas Kappler, Hailiang Dong, Stefan Weyer, Rizlan Bernier‐Latmani · 发表于：Environmental Science & Technology · 年份：2025 · DOI：10.1021/acs.est.5c11748 · 被引用次数：3 · 研究领域：Iron oxide chemistry and applications、Radioactive element chemistry and processing、Geochemistry and Elemental Analysis

High Resolution Image Download MS PowerPoint Slide Iron (oxyhydr)oxides are capable of structurally incorporating and releasing trace elements through Fe 2+ -induced recrystallization. However, estimation of the extent of recrystallization varies among studies using isotopic tracers and those examining the release of occluded trace elements. To provide further insight into the dynamics of Fe 2+ -catalyzed iron (oxyhydr)oxide recrystallization, and to accurately interpret the isotopic and elemental compositions of iron (oxyhydr)oxides in the rock record, we probed the coupled dynamics of goethite isotopic exchange and trace element cycling during Fe 2+ -induced recrystallization. Herein, 57 Fe labeled Fe 2+ was reacted with U(V)-incorporated goethite, and the resulting isotopic and elemental interactions were systematically characterized and modeled. Partial release of incorporated U (3.9%) was observed, which suggested limited recrystallization while Fe isotope measurements suggested nearly complete isotopic mixing after 30 days. A box model incorporating partial and gradual back-reaction estimated an overall goethite recrystallization extent of ∼32.8%, narrowing the gap to the observed U release (3.9%) as compared to the traditional fast back-reaction-only model (88%). This study highlights the role of Fe 2+ -driven recrystallization in controlling trace metal cycling and provides insights into the stability and reactivity of U-incorporated goethite in reducing environments....