Synthesis and characterization of Mn intercalated Mg-Al hydrotalcite

Chengxue Yang; Libing Liao; Guocheng Lv; Limei Wu; Lefu Mei; Zhaohui Li

doi:10.1016/j.jcis.2016.06.057

Synthesis and characterization of Mn intercalated Mg-Al hydrotalcite

J Colloid Interface Sci. 2016 Oct 1:479:115-120. doi: 10.1016/j.jcis.2016.06.057. Epub 2016 Jun 28.

Authors

Chengxue Yang¹, Libing Liao², Guocheng Lv³, Limei Wu¹, Lefu Mei¹, Zhaohui Li⁴

Affiliations

¹ Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing 100083, China.
² Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing 100083, China. Electronic address: clayl@cugb.edu.cn.
³ Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing 100083, China. Electronic address: guochenglv@cugb.edu.cn.
⁴ Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing 100083, China; Geosciences Department, University of Wisconsin - Parkside, Kenosha, WI 53141-2000, USA.

PMID: 27380016
DOI: 10.1016/j.jcis.2016.06.057

Abstract

Mn intercalated hydrotalcite was prepared using a reconstruction method. And Mn intercalation was confirmed by XRD, FTIR, and thermal analyses. The different valences of Mn were present as determined by XPS. Calcination slightly promoted the isomorphic replacement of Mn(2+) and Mn(3+) for Mg(2+) and Al(3+), especially the replacement of Mn(2+) for Mg(2+) and Al(3+), and to some extent, reduced Mn intercalation. Ultrasonic treatment significantly increased Mn intercalation in permanganate form (Mn(7+)), and promoted the replacement of Mn(2+) for Mg(2+) and Al(3+). XRF analysis showed that ultrasonic treatment decreased the unbalanced layer charge of Mn intercalated hydrotalcite, while prolonged calcination increased it. These results may provide guidance on the preparation and application of Mn intercalated hydrotalcite. Extended calcination time and ultrasonic vibration increased the interlayer spacing of hydrotalcite, as a result of reduction in layer charge. As the layer charge was not completely balanced after Mn intercalation, a certain amount of CO3(2-) was re-adsorbed into the interlayer space. Mn-hydrotalcites with different layer charges, different contents of Mn with varying valences are expected to have different performances in the process of adsorption, degradation, and catalysis.

Keywords: Chemical state; Hydrotalcite; Layer charge; Mn intercalation.