Desorption of cesium from granite under various aqueous conditions.
In this work the desorption of cesium ions from crushed granite in synthetic groundwater (GW) and seawater (SW) was investigated. Results were compared with those obtained in deionized water (DW) and in two kinds of extraction solutions, namely: MgCl(2) and NaOAc (sodium acetate). In general, the desorption rate of Cs from crushed granite increased proportionally with initial Cs loadings. Also, amounts of desorbed Cs ions followed the tendency in the order SW>GW>NaOAc approximately equal MgCl(2)>DW solutions. This indicated that the utilization of extraction reagents for ion exchange will underestimate the Cs desorption behavior. Fitting these experimental data by Langmuir model showed that these extraction reagents have reduced Cs uptake by more than 90%, while only less than 1% of adsorbed Cs ions are still observed in GW and SW solutions in comparison to those in DW. Further SEM/EDS mapping studies clearly demonstrate that these remaining adsorbed Cs ions are at the fracture areas of biotite.
Wang
Tsing-Hai
TH
Institute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 300, Taiwan.
Li
Ming-Hsu
MH
Wei
Yuan-Yaw
YY
Teng
Shi-Ping
SP
D000327:Adsorption; D002586:Cesium / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008962:Models, Theoretical; D012822:Silicon Dioxide; D014867:Water
C007886:granite; D014867:Water; D002586:Cesium; D012822:Silicon Dioxide