在性pH值下,二线铁化物转化为戈伊
Fabio E Furcas1, Barbara Lothenbach2, Shishir Mundra1
1Institute for Building Materials, ETH Zürich, 8093 Zürich, Switzerland.
Environmental science & technology
|October 12, 2023
概括
在高度性pH (≥13.0) 时,二线铁化物迅速转化为哥,在pH14.0时半衰期不到5小时. 这种转变对于理解废物中的矿物质形成和环境应用至关重要.
科学领域:
- 地质化学 地质化学
- 材料科学 材料科学 材料科学
- 环境科学 环境科学
背景情况:
- 双线铁酸盐是一种常见的铁氧化氧化物矿物.
- 它转化为更稳定的相,如石,具有环境意义.
- 了解转换动力学是预测矿物质在各种环境中的行为的关键.
研究的目的:
- 在高性条件下 (pH ≥13.0) 调查二线铁酸盐转化为戈伊的过程.
- 量化极端pH对转化速率的影响.
- 阐明控制转化过程的机制.
主要方法:
- 使用了基准和先进的同步仪技术,包括X射线衍射 (XRD),热重力学分析 (TGA) 和X射线吸收光谱学 (XAS).
- 使用感应合等离子光学发射光谱学 (ICP-OES) 监测水性Fe(III) 度.
主要成果:
- 随着pH值的增加,二线铁酸盐的转化半衰期急剧下降,从pH值2.0的几个月降至pH值14.0的5小时以下.
- 第一阶速率常数 (k) 随着pH指数增长,以下是log10 k = log10 k0 + a·pH3.3.
- 证实从溶液中沉戈伊,转化速率受到铁酸再溶解的限制.
结论:
- 高性条件显著加快二线铁化转化为哥.
- 转化机制包括goethite沉,速度受到ferrihydrite溶解的限制.
- 这些发现适用于估计矿山尾矿,放射性废物和水泥材料中的铁化转化.
关键词:
在ICP中,ICP是指ICP.在TGA上,TGA就是TGA.在XASAS中,XAS就是XAS.XRD XRD 在线观看铁是铁的,铁是铁的运动学的动力学.它们的pH值为pH.降水 降水 降水 降水 降水更多相关视频
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