Recycling Mg(OH)2Nanoadsorbent during Treating the Low Concentration of CrVI

作者：Weizhen Liu, Feng Huang, Yongjing Wang, Ting Zou, Jinsheng Zheng, Zhang Lin · 发表于：Environmental Science & Technology · 年份：2011 · DOI：10.1021/es1035199 · 被引用次数：206 · 研究领域：Magnesium Oxide Properties and Applications、Environmental remediation with nanomaterials、Geochemistry and Elemental Analysis

Investigations about how to recycle the deactivated nanomaterials are well-needed. This work was designed to explore the recycling strategy of Mg(OH)(2) nanoadsorbent during treating low concentration of Cr(VI) solution as an example. It was demonstrated that a reversible route between Cr-adsorbed nano-Mg(OH)(2) and Cr-desorbed bulk-MgCO(3) · 3H(2)O can be established by using CO(2) as a phase transformation medium. In each adsorption-desorption cycle, Cr(VI) solution with initial concentration of 10 mg · L(-1) could be enriched over 40 times. An aggregation-induced rapid phase transformation mechanism from nano-Mg(OH)(2) to bulk-MgCO(3) · 3H(2)O was discovered, which was one of the critical factors to ensure the disposing efficiency of this environmental-friendly Cr(VI) disposal system. A pilot-scale experiment was conducted with this strategy to deal with 50 L Cr(VI)-containing simulated industrial wastewater. The enrichment of Cr(VI) and the recycle of nano-Mg(OH)(2) can be successfully achieved simultaneously.