Abstract Zeolite X (ZX) was synthesized by diatomite in a water system, and then the synthetic zeolite was modified by thiourea (TU). The synthetic and modified ZX were characterized by XRD, FT-IR, TG/DTA, elemental analysis (CHNS), FE-SEM, EDX, elemental mapping and N2 adsorption/desorption isotherms, respectively. All the results confirmed that the TU molecules were loaded onto both the exterior and interior surfaces of ZX during the modification process. Compared to the raw ZX, the modified ZX has a higher removal capacity in the Cd(II) removal experiments. In ZX-TU sample, removal of Cd(II) takes place via ion exchange and complexation processes. The maximum adsorption capacity is 92.47 mg/g at 25 °C. This cost-effective zeolite can be a functional material for heavy metal removal.

中文翻译：

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硫脲改性合成沸石X及其对Cd(II)的吸附

摘要 采用硅藻土在水体系中合成沸石X（ZX），然后用硫脲（TU）对合成沸石进行改性。合成和改性的 ZX 分别通过 XRD、FT-IR、TG/DTA、元素分析 (CHNS)、FE-SEM、EDX、元素映射和 N2 吸附/解吸等温线进行表征。所有结果证实，在改性过程中，TU 分子被加载到 ZX 的外表面和内表面。与原始 ZX 相比，改性 ZX 在 Cd(II) 去除实验中具有更高的去除能力。在 ZX-TU 样品中，通过离子交换和络合过程去除 Cd(II)。在 25 °C 时的最大吸附容量为 92.47 mg/g。这种具有成本效益的沸石可以成为去除重金属的功能材料。