期刊
GEOCHIMICA ET COSMOCHIMICA ACTA
卷 73, 期 12, 页码 3579-3592出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.gca.2009.03.032
关键词
-
资金
- Svensk Karnebranselshandtering (SKB)
- EC
- Danish Natural Sciences Research Council (FNU)
- Carlsberg Foundation
Mixed-valent Fe(II),Fe(III)-layered hydroxide, known as green rust, was synthesized from slightly basic, sodium sulphate solutions in an oxygen-free glove box. Solution conditions were monitored with pH and Eh electrodes and optimized to ensure a pure sulphate green-rust phase. The solid was characterised using Mossbauer spectroscopy, X-ray diffraction, scanning electron microscopy and atomic force microscopy. The composition of the solution from which the green rust precipitated was established by mass and absorption spectroscopy. The sulphate form of green rust is composed of brucite-like layers with Fe(II) and Fe(III) in an ordered distribution. The interlayers contain sulphate, water and sodium in an arrangement characteristic for the nikischerite group. The crystal structure is highly disordered by slacking faults. The composition, formula and crystallographic parameters are: NaFe(II)(6)Fe(III)(3)(SO4)(2)(OH)(18)center dot 12H(2)O, space group P-3, a = 9.528(6) angstrom, c = 10.968(8) angstrom and Z = 1. Green rust sodium sulphate, GR(Na,SO4) crystallizes in thin, hexagonal plates. Particles range from less than 50 nm to 2 mu m in diameter and are 40 nm thick or less. The material is redox active and reaction rates are fast. Extremely small particle size and high surface area contribute to rapid oxidation, transforming green rust to an Fe(III)-phase within minutes. (C) 2009 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据