Tianjin Key Laboratory of Agro-environment and Safe-product, Key Laboratory for Environmental Factors Control of Agro-product Quality Safety (Ministry of Agriculture and Rural Affairs), Institute of Agro-environmental Protection, Ministry of Agriculture and Rural Affairs, Tianjin 300191, China.
Tianjin Key Laboratory of Agro-environment and Safe-product, Key Laboratory for Environmental Factors Control of Agro-product Quality Safety (Ministry of Agriculture and Rural Affairs), Institute of Agro-environmental Protection, Ministry of Agriculture and Rural Affairs, Tianjin 300191, China.
Ecotoxicol Environ Saf. 2024 Aug;281:116600. doi: 10.1016/j.ecoenv.2024.116600. Epub 2024 Jun 18.
Arsenic pollution control technology in water was important to ensure environmental health and quality safety of agricultural products. Therefore, the adsorption performance of three adsorbents for chitosan, sepiolite, and Zeolitic Imidazolate Framework-8 (ZIF-8) were investigated in arsenate contaminated water. The results revealed that the adsorption capacity of ZIF-8 was higher than that of chitosan and sepiolite. The analysis of adsorption isotherm models showed that the behavior of ZIF-8 was more consistent with the Langmuir model. Furthermore, the adsorption mechanisms of three adsorbents for arsenate were investigated by Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The analysis of FTIR showed that ZIF-8 maintained the stability of the interaction with arsenate by forming As-O chemical bonds. However, the effect of chitosan and sepiolite with arsenate was mainly physical adsorption. The analysis of XPS showed that the absorption of ZIF-8 with arsenate involved metal sites and nitrogen through the characteristic peak and the change of the binding energy. Furthermore, the impact of microplastics as a widespread coexistence pollutant in the water on adsorbent performance was investigated. The results indicated that the adsorption capacity of ZIF-8 was almost not affected by microplastics. The maximum adsorption amount of arsenate was changed from 73.45 mg/g to 81.89 mg/g. However, the maximum adsorption amount of chitosan and sepiolite decreased by 31.4 % and 11.6 %, respectively. The analysis of FTIR and XPS revealed that ZIF-8 enhances arsenate adsorption by forming N-O-As bonds in the presence of microplastics. This study provides scientific evidence for the management of arsenate pollution in water bodies, especially in complex water bodies containing microplastics.
砷污染控制技术对保障水环境健康和农产品质量安全至关重要。因此，研究了壳聚糖、海泡石和沸石咪唑酯骨架-8（ZIF-8）三种吸附剂对砷酸盐污染水的吸附性能。结果表明，ZIF-8 的吸附容量高于壳聚糖和海泡石。吸附等温线模型分析表明，ZIF-8 的行为更符合朗缪尔模型。此外，通过傅里叶变换红外光谱（FTIR）和 X 射线光电子能谱（XPS）分析了三种吸附剂对砷酸盐的吸附机理。FTIR 分析表明，ZIF-8 通过形成 As-O 化学键保持与砷酸盐相互作用的稳定性。然而，壳聚糖和海泡石与砷酸盐的作用主要是物理吸附。XPS 分析表明，ZIF-8 与砷酸盐的吸附涉及金属位和氮，通过特征峰和结合能的变化。此外，还研究了作为水中普遍共存污染物的微塑料对吸附剂性能的影响。结果表明，ZIF-8 的吸附容量几乎不受微塑料的影响。砷酸盐的最大吸附量从 73.45mg/g 变为 81.89mg/g。然而，壳聚糖和海泡石的最大吸附量分别下降了 31.4%和 11.6%。FTIR 和 XPS 分析表明，在存在微塑料的情况下，ZIF-8 通过形成 N-O-As 键增强了砷酸盐的吸附。该研究为水体中砷污染的管理提供了科学依据，特别是在含有微塑料的复杂水体中。
