State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210023, China.
Environ Sci Technol. 2016 Feb 2;50(3):1447-54. doi: 10.1021/acs.est.5b04630. Epub 2016 Jan 15.
A new nanocomposite adsorbent La-201 of extremely high capacity and specific affinity toward phosphate was fabricated and well characterized, where hydrated La(III) oxide (HLO) nanoclusters were immobilized inside the networking pores of the polystyrene anion exchanger D-201. La-201 exhibited enhanced phosphate adsorption in the presence of competing anions (chloride, sulfate, nitrate, bicarbonate, and silicate) at greater levels (up to molar ratio of 20), with working capacity 2-4 times higher than a commercial Fe(III) oxide-based nanocomposite HFO-201 in batch runs. Column adsorption runs by using La-201 could effectively treat ∼6500 bed volumes (BV) of a synthetic feeding solution before breakthrough occurred (from 2.5 mg P/L in influent to <0.5 mg P/L in effluent), approximately 11 times higher magnitude than that of HFO-201. The exhausted La-201 could be regenerated with NaOH-NaCl binary solution at 60 °C for repeated use without any significant capacity loss. The underlying mechanism for the specific sorption of phosphate by La-201 was revealed with the aid of STEM-EDS, XPS, XRD, and SSNMR analysis, and the formation of LaPO4·xH2O is verified to be the dominant pathway for selective phosphate adsorption by the immobilized nano-HLO. The results indicated that La-201 was very promising in highly efficient removal of phosphate from contaminated waters.
一种对磷酸盐具有超高容量和特异亲和力的新型纳米复合材料吸附剂 La-201 被制备并进行了很好的特性描述，其中水合镧（III）氧化物（HLO）纳米簇被固定在聚苯乙烯阴离子交换剂 D-201 的网络孔隙内。La-201 在存在竞争阴离子（氯离子、硫酸根离子、硝酸根离子、碳酸氢根离子和硅酸根离子）的情况下，在更高的水平（高达 20 的摩尔比）下表现出增强的磷酸盐吸附能力，工作容量比商业 Fe(III) 氧化物基纳米复合材料 HFO-201 高 2-4 倍。使用 La-201 进行的柱吸附运行可以在穿透发生之前有效处理约 6500 个床体积（BV）的合成进料溶液（从进水的 2.5 mg P/L 到出水的 <0.5 mg P/L），大约是 HFO-201 的 11 倍。用过的 La-201 可以在 60°C 下用 NaOH-NaCl 二元溶液再生，重复使用而不会有任何容量损失。通过 STEM-EDS、XPS、XRD 和 SSNMR 分析揭示了 La-201 对磷酸盐特异性吸附的潜在机制，证实了 LaPO4·xH2O 的形成是固定纳米 HLO 选择性吸附磷酸盐的主要途径。结果表明，La-201 在从受污染的水中高效去除磷酸盐方面非常有前景。
