Page 161 - 精细化工2019年第10期

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第 10 期 程福龙，等: Zr 掺杂对 Mg/Al 水滑石磷酸根吸附行为的影响 ·2127·

XRD 分析，结果见图 1 和表 1。吸附磷酸根后，MAZ-3 响最显著。
样品仍然保留原有的类水滑石特征衍射峰，没有观 （3）机理分析结果表明，Mg/Al/Zr 三元类水滑
察到其他相的生成，并且晶胞参数 a 没变，而参数 石吸附磷酸根的过程并非表面沉淀，而是静电吸引
c 减少。以上结果表明，Mg/Al/Zr 类水滑石对磷酸 和阴离子交换共同作用的结果。
根的吸附机理并不是表面沉积，很可能为磷酸根离 （4）本研究发现共存阴离子对 Mg/Al/Zr 类水滑
子与类水滑石层板间的静电相互作用以及与层间阴 石去磷效果影响较大，如何改性 Mg/Al/Zr 类水滑石
离子的离子交换作用。为了进一步证实此观点，对 来提高其对磷酸盐的选择性将是下一步研究重点，旨
吸附磷酸根前后的 MAZ-3 样品进行了红外分析，结 在为该材料应用于实际废水处理领域奠定理论基础。
果见图 8。
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