Fe(II) interaction with cement phases was studied by means of co-precipitation and sorption experiments in combination with X-ray absorption fine structure (XAFS) spectroscopy. Oxidation of Fe(II) was fast in alkaline conditions and therefore, a methodology was developed which allowed Fe(II) to be stabilised in the sorption experiments and to prepare samples for spectroscopy. X-ray diffraction (XRD) of the co-precipitation samples showed uptake of a small portion of Fe(II) by calcium-silicate-hydrates (C-S-H) in the interlayer indicated by an increase in the interlayer spacing. Fe(II) incorporation by AFm phases was not indicated. Wet chemical experiments using ⁵⁵Fe radiotracer revealed linear sorption of Fe(II) irrespective of the Ca/Si ratio of C-S-H and equilibrium pH. The K_d values for Fe(II) sorption on C-S-H are more than three orders of magnitude lower as compared to Fe(III), while they are comparable to those of other bivalent metal cations. XAFS spectroscopy showed Fe(II) binding by C-S-H in an octahedral coordination environment. The large number of neighbouring atoms rules out the formation of a single surface-bound Fe(II) species. Instead the data suggest presence of Fe(II) in a structurally bound entity. The data from XRD and XAFS spectroscopy suggests the presence of both surface- and interlayer-bound Fe(II) species.

通过共沉淀和吸附实验结合 X 射线吸收精细结构 (XAFS) 光谱，研究了 Fe(II) 与水泥相的相互作用。Fe(II) 在碱性条件下的氧化速度很快，因此，开发了一种方法，使 Fe(II) 在吸附实验中稳定并制备用于光谱的样品。共沉淀样品的 X 射线衍射 (XRD) 显示，夹层中的硅酸钙水合物 (CSH) 吸收了一小部分 Fe(II)，这表明夹层间距的增加。没有表明 AFm 相掺入 Fe(II)。使用⁵⁵ Fe 放射性示踪剂的湿化学实验揭示了 Fe(II) 的线性吸附，而与 CSH 的 Ca/Si 比和平衡 pH 值无关。在K _d与 Fe(III) 相比，CSH 上的 Fe(II) 吸附值低三个数量级以上，而它们与其他二价金属阳离子的吸附值相当。XAFS 光谱显示 CSH 在八面体配位环境中结合 Fe(II)。大量相邻原子排除了单一表面结合 Fe(II) 物质的形成。相反，数据表明在结构结合的实体中存在 Fe(II)。来自 XRD 和 XAFS 光谱的数据表明存在表面和层间结合的 Fe(II) 物质。