Selenium Sequestration in a Cationic Layered Rare Earth Hydroxide: A Combined Batch Experiments and EXAFS Investigation

doi:10.1021/acs.est.7b02006

CORC > 上海应用物理研究所 > 中国科学院上海应用物理研究所 > 中科院上海应用物理研究所2011-2017年

	Selenium Sequestration in a Cationic Layered Rare Earth Hydroxide: A Combined Batch Experiments and EXAFS Investigation
	Zhu, L; Zhang, LJ; Li, J; Zhang, D; Chen, LH; Sheng, DP; Yang, ST; Xiao, CL; Wang, JQ; Chai, ZF
刊名	ENVIRONMENTAL SCIENCE & TECHNOLOGY
	2017
卷号	51 期号:15 页码:8606-8615
关键词	Anion-exchange Materials Adsorption Mechanisms Intercalation Hosts Sulfate Adsorption Phosphate Removal Aqueous-solutions Gd-lu Selenate Water Sorption
ISSN号	0013-936X
DOI	10.1021/acs.est.7b02006
文献子类	期刊论文
英文摘要	Selenium is of great concern owing to its acutely toxic characteristic at elevated dosage and the long-term radiotoxicity of Se-79. The contents of selenium in industrial wastewater, agricultural runoff, and drinking water have to be constrained to a value of 50 mu g/L as the maximum concentration limit. We reported here the selenium uptake using a structurally well-defined cationic layered rare earth hydroxide, Y-2(OH)(5)Cl center dot 1.5H(2)O. The sorption kinetics, isotherms, selectivity, and desorption of selenite and selenate on Y-2(OH)(5)Cl center dot 1.5H(2)O at pH 7 and 8.5 were systematically investigated using a batch method. The maximum sorption capacities of selenite and selenate are 207 and 124 mg/g, respectively, both representing the new records among those of inorganic sorbents. In the low concentration region, Y-2(OH)(5)Cl center dot 1.5H(2)O is able to almost completely remove selenium from aqueous solution even in the presence of competitive anions such as NO3-, Cl-, CO32-, SO42-, and HPO42-. The resulting concentration of selenium is below 10 mu g/L, well meeting the strictest criterion for the drinking water. The selenate on loaded samples could be desorbed by rinsing with concentrated noncomplexing NaCl solutions whereas complexing ligands have to be employed to elute selenite for the material regeneration. After desorption, Y-2(OH)(5)Cl center dot 1.5H(2)O could be reused to remove selenate and selenite. In addition, the sorption mechanism was unraveled by the combination of EDS, FT-IR, Raman, PXRD, and EXAFS techniques. Specifically, the selenate ions were exchanged with chloride ions in the interlayer space, forming outer-sphere complexes. In comparison, besides anion exchange mechanism, the selenite ions were directly bound to the Y3+ center in the positively charged layer of [Y-2(OH)(5)(H2O)](+) through strong bidentate binuclear inner-sphere complexation, consistent with the observation of the higher uptake of selenite over selenate. The results presented in this work confirm that the cationic layered rare earth hydroxide is an emerging and promising material for efficient removal of selenite and selenate as well as other anionic environmental pollutants.
WOS关键词	ANION-EXCHANGE MATERIALS ; ADSORPTION MECHANISMS ; INTERCALATION HOSTS ; SULFATE ADSORPTION ; PHOSPHATE REMOVAL ; AQUEOUS-SOLUTIONS ; GD-LU ; SELENATE ; WATER ; SORPTION
语种	英语
WOS记录号	WOS:000406982600044
内容类型	期刊论文
源URL	[http://ir.sinap.ac.cn/handle/331007/28810]
专题	上海应用物理研究所_中科院上海应用物理研究所2011-2017年
推荐引用方式 GB/T 7714	Zhu, L,Zhang, LJ,Li, J,et al. Selenium Sequestration in a Cationic Layered Rare Earth Hydroxide: A Combined Batch Experiments and EXAFS Investigation[J]. ENVIRONMENTAL SCIENCE & TECHNOLOGY,2017,51(15):8606-8615.
APA	Zhu, L.,Zhang, LJ.,Li, J.,Zhang, D.,Chen, LH.,...&Wang, S.(2017).Selenium Sequestration in a Cationic Layered Rare Earth Hydroxide: A Combined Batch Experiments and EXAFS Investigation.ENVIRONMENTAL SCIENCE & TECHNOLOGY,51(15),8606-8615.
MLA	Zhu, L,et al."Selenium Sequestration in a Cationic Layered Rare Earth Hydroxide: A Combined Batch Experiments and EXAFS Investigation".ENVIRONMENTAL SCIENCE & TECHNOLOGY 51.15(2017):8606-8615.