纳米封闭增加了化氧化与酸盐的亲和力:表面复杂化建模研究研究
Pengfei Shen1, Siyuan Pan1, Xianfeng Huang2
1State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, 210023, China.
Chemosphere
|December 8, 2023
概括
纳米级的化氧化 (HZO) 在D201离子交换器中封装时显示出增强的酸吸附. 这种纳米封闭效应显著提高了化学结合亲和力,以有效地净化地下水.
科学领域:
- 环境科学 环境科学
- 材料科学 材料科学 材料科学
- 化学 化学 化学
背景情况:
- 纳米级的化氧化 (HZO) 是通过内部球协调从地下水中去除酸盐的有希望的.
- 氧化的吸附机制,特别是酸的吸附机制,需要进一步探索实际的水处理应用.
研究的目的:
- 为了研究HZO上的Zr-As协调配置.
- 用HZO纳米粒子 (NP) 在D201离子交换器中量化纳米封闭对酸盐吸附的影响.
- 确定内在协调常数 (Kintr) 并比较吸附能力.
主要方法:
- 表面复杂化建模 (SCM),X射线光电子光谱学 (XPS) 和里埃变换红外光谱学 (FT-IR) 用于识别Zr-As配置.
- 电位计定位在HZO上特征表面基组.
- 批量吸附实验比较赤裸的HZO与HZO@D201纳米复合材料在不同的pH和离子强度下.
主要成果:
- 与赤裸的HZO相比,纳米复合材料 (HZO@D201) 在广泛的pH (3-10) 和离子强度 (0.001-0.1 M NaNO3) 范围内显示出更高的酸盐吸附能力.
- 在SCM模拟中,在pH值3-6时确定了二质化单单核 (MM-H2) 为主导配置,在pH值>7时确定了二质化双核 (BB-H0) 为主导配置.
- HZO@D201的内在协调常数 (Kintr) 比赤裸裸的HZO高得多,这表明由于纳米封闭而增强的化学结合亲和力.
结论:
- 在D201矩阵内的纳米封闭大大提高了HZO的酸盐吸附性能.
- 该研究提供了一个热力学框架,用于评估纳米复合材料吸附剂中纳米封闭效应.
- 为HZO提供了参考协调平衡常数,用于研究和实际的水处理应用.
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