稀土离子在蒙莫里隆石层间空间中的结构和流动性:一个分子动力学研究
Caorui Wang1, Yingchun Zhang1, Xiandong Liu1
1State Key Laboratory for Mineral Deposits Research, School of Earth Science and Engineering, Nanjing University, Nanjing 210023, China. xiandongliu@nju.edu.cn.
Physical chemistry chemical physics : PCCP
|October 7, 2024
概括
分子动力学模拟显示,稀土元素 (REEs) 在蒙莫里隆石中间层中形成稳定的外层复合体. 这澄清了离子吸附型沉积物 (IAD) 中的REE吸附机制,并有助于提取技术的发展.
科学领域:
- 地质化学 地质化学
- 材料科学 材料科学 材料科学
- 计算化学计算化学
背景情况:
- 离子吸附型沉积物 (IAD) 是稀土元素 (REE) 的主要来源.
- 在IAD中,REEs主要在粘土矿物中进行丰富.
- 在粘土矿物间层中,REEs的精确吸附机制尚不清楚.
研究的目的:
- 为了研究REE插入的蒙莫里隆石的间层结构和动态.
- 阐明粘土矿物质中轻质 REE (LREE) 和重质 REE (HREE) 的吸附机制.
主要方法:
- 使用分子动力学 (MD) 模拟来建模REE-montmorillonite系统.
- 雇佣的La3+和Lu3+作为LREEs和HREEs的代表性.
- 分析了层间结构,协调环境和离子流动性.
主要成果:
- 确定了LREE和HREE-montmorillonite的稳定双水合状态,基底间距为~16.1 Å.
- 确定REE离子通过与蒙特莫里隆石基底表面的键形成外部球体复合体.
- 与水溶液相比,观察到间隔的REEs的流动性降低,对La3+ (9倍) 和Lu3+ (8倍) 有不同的协调号码.
结论:
- 这项研究提供了分子层面的了解REE吸附在蒙特莫里隆石中间层.
- 调查结果澄清了IADs中的REE丰富和动员过程.
- 结果为开发改进的REE提取技术提供了基础.
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