DOI: 10.1038/ngeo1825
论文题名: Hydrogen generation from low-temperature water-rock reactions
作者: Mayhew L.E. ; Ellison E.T. ; McCollom T.M. ; Trainor T.P. ; Templeton A.S.
刊名: Nature Geoscience
ISSN: 17520894
出版年: 2013
卷: 6, 期: 6 起始页码: 478
结束页码: 484
语种: 英语
Scopus关键词: crystal structure
; high temperature
; hydration
; hydrogen
; hydrothermal vent
; iron oxide
; low temperature
; microbial community
; oxidation
; speciation (chemistry)
; spinel
; thermal spring
; ultramafic rock
; water-rock interaction
; X-ray fluorescence
; XANES spectroscopy
英文摘要: Hydrogen is commonly produced during the high-temperature hydration of mafic and ultramafic rocks, owing to the oxidation of reduced iron present in the minerals. Hydrothermal hydrogen is known to sustain microbial communities in submarine vent and terrestrial hot-spring systems. However, the rates and mechanisms of hydrogen generation below temperatures of 150°C are poorly constrained. As such, the existence and extent of hydrogen-fuelled ecosystems in subsurface terrestrial and oceanic aquifers has remained uncertain. Here, we report results from laboratory experiments in which we reacted ground ultramafic and mafic rocks and minerals - specifically peridotite, pyroxene, olivine and magnetite - with anoxic fluids at 55 and 100°C, and monitored hydrogen gas production. We used synchrotron-based micro-X-ray fluorescence and X-ray absorption near-edge structure spectroscopy to identify changes in the speciation of iron in the materials. We report a strong correlation between molecular hydrogen generation and the presence of spinel phases - oxide minerals with the general formula [M2+M23+]O 4 and a cubic crystal structure - in the reactants. We also identify Fe(III)-(hydr)oxide reaction products localized on the surface of the spinel phases, indicative of iron oxidation. We propose that the transfer of electrons between Fe(II) and water adsorbed to the spinel surfaces promotes molecular hydrogen generation at low temperatures. We suggest that these localized sites of hydrogen generation in ultramafic aquifers in the oceanic and terrestrial crust could support hydrogen-based microbial life. © 2013 Macmillan Publishers Limited. All rights reserved.
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/106787
Appears in Collections: 气候减缓与适应 科学计划与规划
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作者单位: Department of Geological Sciences, UCB 399, University of Colorado-Boulder, Boulder, CO 80309, United States; Laboratory for Atmospheric and Space Physics, UCB 392, University of Colorado-Boulder, Boulder, CO 80309, United States; Department of Chemistry and Biochemistry, University of Alaska-Fairbanks, PO Box 756160, Fairbanks, AK 99775, United States
Recommended Citation:
Mayhew L.E.,Ellison E.T.,McCollom T.M.,et al. Hydrogen generation from low-temperature water-rock reactions[J]. Nature Geoscience,2013-01-01,6(6)