Caesium incorporation and retention in illite interlayers.

Saved in:
Bibliographic Details
Title: Caesium incorporation and retention in illite interlayers.
Authors: Fuller, Adam J.1, Shaw, Samuel2, Ward, Michael B.3, Haigh, Sarah J.4,5, Mosselmans, J. Frederick W.6, Peacock, Caroline L.1, Stackhouse, Stephen1, Dent, Andrew J.6, Trivedi, Divyesh7, Burke, Ian T.1 i.t.burke@leeds.ac.uk
Source: Applied Clay Science. May2015, Vol. 108, p128-134. 7p.
Subjects: Cesium, Illite, Sorption, Clay minerals, Transmission electron microscopy, Radioactive substances
Abstract: Radioactive caesium (chiefly 137 Cs) is a major environmental pollutant. The mobility of Cs in temperate soils is primarily controlled by sorption onto clay minerals, particularly the frayed edges of illite interlayers. This paper investigates the adsorption of Cs to illite at the molecular scale, over both the short and long term. Transmission electron microscopy (TEM) images showed that after initial absorption into the frayed edges, Cs migrated into the illite interlayer becoming incorporated within the mineral structure. Caesium initially exchanged with hydrated Ca at the frayed edges, causing them to collapse. This process was irreversible as Cs held in the collapsed interlayers was not exchangeable with Ca. Over the long term Cs did not remain at the edge of the illite crystals, but diffused into the interlayers by exchange with K. Results from extended X-ray absorption fine structure spectroscopy (EXAFS) and density functional theory modelling confirmed that Cs was incorporated into the illite interlayer and revealed its bonding environment. [ABSTRACT FROM AUTHOR]
Copyright of Applied Clay Science is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
Description
Abstract:Radioactive caesium (chiefly 137 Cs) is a major environmental pollutant. The mobility of Cs in temperate soils is primarily controlled by sorption onto clay minerals, particularly the frayed edges of illite interlayers. This paper investigates the adsorption of Cs to illite at the molecular scale, over both the short and long term. Transmission electron microscopy (TEM) images showed that after initial absorption into the frayed edges, Cs migrated into the illite interlayer becoming incorporated within the mineral structure. Caesium initially exchanged with hydrated Ca at the frayed edges, causing them to collapse. This process was irreversible as Cs held in the collapsed interlayers was not exchangeable with Ca. Over the long term Cs did not remain at the edge of the illite crystals, but diffused into the interlayers by exchange with K. Results from extended X-ray absorption fine structure spectroscopy (EXAFS) and density functional theory modelling confirmed that Cs was incorporated into the illite interlayer and revealed its bonding environment. [ABSTRACT FROM AUTHOR]
ISSN:01691317
DOI:10.1016/j.clay.2015.02.008