在酸酸水泥中Zn2+的固化/稳定行为:实验和密度功能理论研究实验
Renjie Mi1, Zhibin Zhang2, Weiming Ji3
1Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China.
Environmental research
|May 28, 2023
概括
将离子 (Zn2+) 添加到酸水泥 (MKPC) 中,会减缓其定并降低强度. 然而,的泄漏毒性仍然远低于安全标准.
科学领域:
- 材料科学 材料科学 材料科学
- 无机化学 无机化学
- 建筑材料 建筑材料
背景情况:
- 在酸水泥 (MKPC) 中离子 (Zn2+) 的固化和稳定机制尚不清楚.
- 了解这些行为对于优化MKPC性能和安全至关重要.
研究的目的:
- 为了研究MKPC中Zn2+的固化/稳定行为.
- 阐明Zn2+对MKPC的水化产品和结构特征的影响.
- 为了评估MKPC中Zn2+的泄漏毒性.
主要方法:
- 对MKPC进行实验分析,添加了各种Zn2+.
- 密度函数理论 (DFT) 计算以确定结合能.
- 晶体特性分析和热分解研究.
- 根据中国和欧洲标准进行液毒性测试.
主要成果:
- 由于延迟MgKPO的形成,MKPC的压缩强度随着Zn2+的添加而降低.
- DFT结果表明,与水化产品中的Mg相比,Zn2+的结合能更低.
- 2+主要形成Zn2OHPO4,在190-350°C之间分解,对MgKPO6H的结构影响最小.
- 微观结构从表状转向不规则的镜晶体;浸出毒性明显低于标准.
结论:
- 2+的添加会通过干扰水合而对MKPC的早期强度发展产生负面影响.
- 尽管结构发生了变化,但MKPC中的Zn2+具有较低的漏毒性,符合严格的国际标准.
- 这些发现提供了关于Zn2+在MKPC中的作用的见解,指导了未来的材料开发.
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