High Li-Ion Selectivity of Five-Coordinate Layered Titanate K2Ti2O5

Selectivity of ion exchangers is an important topic in adsorption science owing to its specific application in resource recovery and environmental remediation. In this study, the cation exchange property of the submillimeter-sized five-coordinate K2Ti2O5 (KTO) crystals is demonstrated. Adsorption is...

Ausführliche Beschreibung

Bibliographische Detailangaben
Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1992. - 38(2022), 43 vom: 01. Nov., Seite 13288-13295
1. Verfasser: Hayashi, Fumitaka (VerfasserIn)
Weitere Verfasser: Tatewaki, Nanako, Sudare, Tomohito, Terashima, Chiaki, Teshima, Katsuya
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2022
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article
Beschreibung
Zusammenfassung:Selectivity of ion exchangers is an important topic in adsorption science owing to its specific application in resource recovery and environmental remediation. In this study, the cation exchange property of the submillimeter-sized five-coordinate K2Ti2O5 (KTO) crystals is demonstrated. Adsorption isotherm measurements were performed on KTO crystals ion-exchanged with alkali metal cations including Li+, Na+, Rb+, and Cs+. The maximum adsorption amounts of Li+, Na+, Rb+, and Cs+ on KTO were 2.70, 1.15, 0.59, and 0.42 mmol g-1, respectively, which is contradictory to the "normal" selectivity sequence (Cs+ > Rb+ > K+ > Na+ > Li+) of conventional ion exchangers, including clays and organic resins. The Kielland plots for the Li+ and Cs+ exchange experiments showed preferential Li+ adsorption on KTO, which supports the high Li+ selectivity. The interlayer distance for M+-exchanged KTO (M = Li, Na, Rb, and Cs) was dependent on cation type. Raman and X-ray absorption near-edge structure spectroscopic analyses of the KTO samples indicated that certain Ti species in KTO underwent hydrolysis, and thereby formed hydroxyl groups on the KTO surface during ion exchange. The origin of the high Li+ selectivity of KTO is discussed herein based on experimental characterization results
Beschreibung:Date Revised 01.11.2022
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1520-5827
DOI:10.1021/acs.langmuir.2c02443