在无毒条件下维维安石溶解的速率和机制
Rouven Metz1, Naresh Kumar2, Walter D C Schenkeveld2
1Centre for Microbiology and Environmental Systems Science, Department for Environmental Geosciences, University of Vienna, Josef-Holaubek-Platz 2, 1090 Vienna, Austria.
Environmental science & technology
|November 4, 2023
概括
维维亚尼特是一种可再生源,在pH值较高时,可溶性和溶解率降低. 一个由缺陷驱动的机制解释了它的行为,以桥解离为速度限制的步骤.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 矿物学是一门学科.
背景情况:
- 维维亚尼特 (Fe(II)3(PO4)2·8H2O) 是一个潜在的可再生源.
- 了解维亚尼特溶解对于其作为P水槽或来源的应用至关重要.
- 缺乏关于vivianite分子水平溶解的机械洞察力.
研究的目的:
- 量化确定vivianite溶解速度和机制.
- 为了研究pH值和温度对无氧条件下的vivianite溶解的影响.
- 阐明对维亚尼特生物利用性的热力学和动力学控制.
主要方法:
- 进行了受控批量和流通实验.
- 维维亚尼特溶解被研究为pH值和温度的函数.
- 溶解速度和机制被定量确定.
主要成果:
- 随着pH的增加,vivianite的可溶性和溶解率显著下降.
- 在性pH (>7) 时观察到非静态度溶解.
- 提出了一个缺陷驱动的溶解机制,具有较低的激活能量 (20.3 kJ mol-1).
结论:
- 维维亚尼特的溶解是通过溶液和状态进行热力学控制的.
- 桥解离是vivianite溶解中可能决定速度的步骤.
- 维维安石的行为依赖于pH值,影响其在循环中的作用.
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