Cesium sorption to illite as affected by oxalate

Laura A. Wendling, James B. Harsh, Carl D. Palmer, Melinda A. Hamilton, Markus Flury

Research output: Contribution to journalArticleScientificpeer-review

25 Citations (Scopus)


Cesium uptake by plants depends on adsorption/desorption reactions in the soil, as well as root uptake processes controlled by the plant. In this study, sorption and desorption of Cs+ on reference illite (lMt-1) was investigated in the presence of oxatate to gain understanding of mechanisms by which plant root exudates may influence Cs+ bioavailability in micaceous soils. Cesium sorption on illite decreased significantly as oxalate concentration increased from 0.4 to 2 mM. Cesium desorption from illite increased significantly with increasing oxalate concentration. Desorption of Cs+ by exchange with Na+, Ca2+ and Mg2+ was significantly enhanced in the presence of oxalate as selectivity for Cs-decreased with respect to these ions in the presence of oxalate. On the other hand, oxalate had little effect on the Cs+/K+ selectivity coefficient. This suggests that oxalate treatments increase the relative proportion of exchange sites that are not highly selective for Cs+ and K+; e.g. 'planar' sites. The results indicate that oxalate plays an important role in Cs+ binding on illite and, therefore, plant rhizosphere chemistry is likely to alter Cs+ bioavailability in micaceous soils.

Original languageEnglish
Pages (from-to)375-381
Number of pages7
JournalClays and Clay Minerals
Issue number3
Publication statusPublished - 1 Jun 2004
MoE publication typeA1 Journal article-refereed


  • Frayed-edge sites
  • Phytoremediation
  • Rhizosphere
  • Weathering


Dive into the research topics of 'Cesium sorption to illite as affected by oxalate'. Together they form a unique fingerprint.

Cite this