A novel halloysite-CeOx nanohybrid for efficient arsenic removal
A novel halloysite-CeOx nanohybrid for efficient arsenic removal
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一种新型埃洛石-CeOx纳米杂化物，可有效去除砷
DOI：
10.1016/j.clay.2020.105450
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发表时间：
2020
影响因子：
5.6
通讯作者：
Zhou Junming
中科院分区：
文献类型：
--
作者：
Song Yaran;Yuan Peng;Du Peixin;Deng Liangliang;Wei Yanfu;Liu Dong;Zhong Xuemin;Zhou Junming
采用氧化还原沉淀法制备了埃洛石-CeOx（x= 1.5-2.0）纳米复合材料，并对所得材料的As（III）去除性能进行了评价。这些复合材料是通过将CeO 2纳米颗粒负载在化学改性的埃洛石基底上形成的。埃洛石的改性使用一个简单的NaOH处理显着增加的内表面和内部的羟基。由于静电相互作用，这些增加的基团显著增强了CeO 2纳米颗粒涂层的分散性。优化后的Hal0.01Ce复合材料的比表面积和孔容分别为91.1m2/g和0.16cm3/g。该复合材料表现出优异的As（III）吸附容量（209.3 mg/g CeO 2），远高于未改性的埃洛石-CeOx复合材料（158.5 mg/g CeO 2）和无负载CeO 2纳米颗粒（61.9 mg/g）。As（III）在该复合材料上的吸附机理包括形成表面络合物和部分As（III）的氧化以及随后的As（V）吸附。此外，Hal0.01Ce复合材料也具有选择性吸附As（III）共存离子的存在下，并保持91.4%的As（III）的去除率后，三个再生周期。这些结果表明，这种复合材料可以作为一个潜在的候选人，从污染的水中去除As（III）。
In this work, halloysite-CeOx(x= 1.5–2.0) nanocomposites were prepared using a redox-precipitation method, and the As(III) removal performance of the obtained materials was evaluated. These composites were formed by supporting CeO2nanoparticles on the chemically modified halloysite substrate. The modification of halloysite using a facile NaOH treatment dramatically increased the inner-surface and inner hydroxyl groups. These increased groups significantly enhanced the dispersion of the coating of CeO2nanoparticles due to electrostatic interactions. The specific surface area and pore volume of the optimized Hal0.01Ce composite was 91.1 m2/g and 0.16 cm3/g, respectively. This composite exhibited an excellent As(III) adsorption capacity (209.3 mg/g CeO2), which was much higher than the unmodified halloysite-CeOxcomposite (158.5 mg/g CeO2) and unsupported CeO2nanoparticles (61.9 mg/g). The As(III) adsorption mechanisms on this composite involved the formation of surface complexes and oxidation of partial As(III) followed by As(V) adsorption. In addition, the Hal0.01Ce composite also possessed selective adsorption for As(III) in the presence of coexisting ions and maintained 91.4% of the As(III) removal efficiency after three regeneration cycles. These results demonstrate that this composite can be used as a potential candidate for As(III) removal from contaminated water.