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arXiv · 1010.3852

Reflexion Mössbauer analysis of the in situ oxidation products hydroxycarbonate green rust

Sebastien Naille·Mustapha Abdelmoula·Didier Louber·Paul Moulin Jean·Christian Ruby
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Abstract

The purpose of this study is to determine the nature of the oxidation products of FeII-III hydroxycarbonate FeII4FeIII2(OH)12CO3~3H2O (green rust GR(CO32-)) by using the miniaturised Mössbauer spectrometer MIMOS II. Two Mössbauer measurements methods are used: method (i) with green rust pastes coated with glycerol and spread into Plexiglas sample holders, and method (ii) with green rust pastes in the same sample holders but introduced into a gas-tight cell with a beryllium window under a continuous nitrogen flow. Method (ii) allows us to follow the continuous deprotonation of GR(CO32-) into the fully ferric deprotonated form FeIII6O4(OH)8CO3~3H2O by adding the correct amount of H2O2, without any further oxidation or degradation of the samples.

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Sebastien Naille, Mustapha Abdelmoula, Didier Louber, Paul Moulin Jean, Christian Ruby. 2010-10-19. Reflexion Mössbauer analysis of the in situ oxidation products hydroxycarbonate green rust. https://doi.org/10.1088/1742-6596%2F217%2F1%2F012084

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