[Paper]CuHCFによる電気化学Cs回収の機構/Mechanism of electrochemical Cs uptake by CuHCF

Thermodynamics and Mechanism Studies on Electrochemical Removal of Cesium Ions from Aqueous Solution Using a Nanoparticle Film of Copper Hexacyanoferrate
CuHCFナノ粒子膜による電気化学的Csイオン回収に関する熱力学と機構

Rongzhi Chen, Hisashi Tanaka*, Tohru Kawamoto, Miyuki Asai, Chikako Fukushima, Masato Kurihara, Manabu Ishizaki, Masayuki Watanabe, Makoto Arisaka, and Takuya Nankawa

ACS Appl. Mater. Interfaces, 2013, 5, pp 12984–12990
DOI: 10.1021/am403748b

Received 09/02, 2013, Accepted 12/02, 2013

Properties of Cu-HCF^III nanoparticle (XRD, EDX, SEM, and AFM) /使用したCuHCF^III薄膜の物性(XRD, EDX,AFM,SEM像)

 Nanoparticle (NPs) film of copper hexacyanoferrate (CuHCF^III) was developed for electrochemically cesium separation from wastewater. Different form the electro- or chemical deposited films, CuHCF^III NPs were firstly covered with ferrocyanide anions, so that they can be well dispersed in water and formed ink. Then CuHCF^III NPs can be uniformly coated by simple wet printing methods, so it is feasible to prepare NPs film of any sizes, or any patterns at low cost. This process provided a promising technology for preparing large scale electrodes for sequential removal of Cs from wastewater in the columns. Cs separation can be controlled by an electrically switched ion exchange (ESIX) system. Effect of temperatures, and ionic strength on Cs removal was investigated. Thermodynamics results showed that Cs adsorption process was exothermic in nature and favored at low temperature. Ionic strength study indicated the CuHCF^III film can selectively separate Cs in wide ionic strength range from 1 × 10^–4 to 1 × 10^–1 M Na⁺. XPS results demonstrated that the electrochemical oxidation–reduction of Fe (II/III) made contributions to Cs separation.

CuHCFのナノ粒子薄膜を利用した水溶液からのCsイオン吸着についてそのメカニズムを詳細に検討しました。この反応は低温でよく進行し、Fe(II/III)の酸化還元反応に伴い起こっていると考えられます。
このシステムは繰り返しCsを吸脱着することが可能で、次世代のCs吸着システムとしての開発を目指しています。

Reprinted with permission. Copyright 2013 American Chemical Society.