Electrochemical Cs removal and crystal formation from Fukushima weathered biotite in molten NaCl-CaCl![$$_{2}$$](/search/images/ERPXWMT3EQ.gif)
Honda, Mitsunori
; Goto, Takuya*; Sakanaka, Yoshihide*; Yaita, Tsuyoshi; Suzuki, Shinichi*
The possibility of removal and controlling crystal formation from weathered biotite (WB) in clay minerals were investigated using molten salt electrochemistry (EC) in molten NaCl-CaCl
under an electrochemical reductive reaction. Cyclic Voltammogram (CV) measurements were performed in the range of +0.5 V to -2.2 V. Several peaks were confirmed in the CV spectra. The peak at -1.4 V represents a reduction reaction of Fe in WB, so we conducted an experiment at -1.4 V for 2 h to reduce Iron (Fe). The Cs removal rate after EC treatment was determined by X-ray fluorescence analysis, and almost 100% Cs removal was confirmed. To understand the effect of the reductive reaction, we performed X-ray Adsorption Fine Structure (XAFS) analysis. Before EC treatment, the Fe in WB was present as a mixture of Fe
and Fe
. After EC treatment, the presence of Fe
was confirmed by XAFS analysis. Based on this finding, EC treatment is effective for reducing Fe in WB. This result indicated that Fe
O
formation was suppressed, and the reduction reaction was effective for controlling crystal formation.