文献类型：期刊文献

英文题名：Effects of excessive lithium deintercalation on Li+ adsorption performance and structural stability of lithium/aluminum layered double hydroxides

作者：Zhong, Jing[1,2];Lin, Sen[1,3];Yu, Jianguo[1,3]

机构：[1]East China Univ Sci & Technol, Natl Engn Res Ctr Integrated Utilizat Salt Lake R, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Engn Res Ctr Salt Lake Resources Proc Engn, Minist Educ, Shanghai 200237, Peoples R China;[3]East China Univ Sci & Technol, State Environm Protect Key Lab Environm Risk Asse, Shanghai 200237, Peoples R China

年份：2020

卷号：572

起止页码：107

外文期刊名：JOURNAL OF COLLOID AND INTERFACE SCIENCE

收录：;EI(收录号：20201408371315);WOS:【SCI-EXPANDED(收录号:WOS:000529798100011)】；

基金：This work was sponsored by the National Natural Science Foundation of China (21978094, 51704121), National Key R&D Program of China (2018YFC0604805), and Major Science and Technology Projects of Qinghai Province (2019-GX-A7).

语种：英文

外文关键词：Lithium aluminum layered double; hydroxides; Excessive lithium deintercalation; Lithium adsorption; Gibbsite; Structural stability

摘要：Lithium/aluminum layered double hydroxides (Li/Al-LDHs) have been industrially proven to be recyclable lithium adsorbents that do not dissolve upon elution, although they are hypersensitive to lithium deintercalation. In this study, the Li+ adsorption performances and structural stabilities of Li/Al-LDHs samples with different lithium deintercalation intensities are comprehensively investigated and compared to expose the influence of excessive lithium deintercalation. The characterization results demonstrate that Li/Al-LDHs are inclined to transform to gibbsite under excessive lithium deintercalation. Moreover, this transformation is enhanced by a long deintercalation time at 80 degrees C in deionized water because the layered structure of Li/Al-LDHs collapses upon reduction of the lithium content. The Li+ adsorption kinetics and isotherms reveal that excessive lithium deintercalation has no effect on the adsorption pathway and rate, while the adsorption capacity fluctuates with increased lithium loss on account of the conflict between the generation of Li+ active sites and structural damage. Adsorption experiments at different pH values show that a neutral pH is more favorable because an acidic or alkaline condition leads to the undesirable formation of a gibbsite or amorphous phase in Li/Al-LDHs during adsorption. In addition, the presence of Mg2+ has a significant effect on the lithium adsorption capacity of Li/Al-LDHs. The adsorption capacities of Li/Al-LDHs samples with different lithium deintercalation intensities are all dramatically enhanced by a high Mg2+ concentration, reflecting the promising potential application of Li/Al-LDHs in Li+ extraction from low-grade brines with high Mg/Li ratios. (C) 2020 Elsevier Inc. All rights reserved.