Electrosorption can be used for both desalination of seawater and high value element ions enrichment, which has attracted more and more attentions because of its merits of low energy consumption, no pollution and inexpensive. The research focuses on the preparation of novel electrodes and selective electrosorption properties. In this paper, biomass carbon aerogel was prepared by hydrothermal-freeze drying- carbonization method using pomelo peel as raw material. A composite electrosorption electrode was obtained using pomelo peel-based carbon aerogel (PCA) as main component. The surface morphology, crystal structure, specific surface area and functional groups were characterized by Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), Brunauer Emmett Teller (BET) and Fourier Transform Infrared Spectroscopy (FTIR). Then the effects of coexisted alkali/alkaline earth metal ions on the adsorption of Rb+ and Cs+ were studied. The pomelo peel-based carbon aerogel-manganese dioxide (PCA-MnO2) composite electrode shows good adsorption performance on Rb+ and Cs+. When alkali and alkaline earth metal ions coexist, PCA-MnO2 composite electrode exhibits the highest adsorption selectivity of Mg2+. The research content in this work broadens the source of electrosorption electrode and provides a reference for the study of competitive adsorption of alkali/alkaline earth metal ions.

Yaoqiang Hu, Min Guo, Xiushen Ye, Quan Li, Haining Liu, Zhijian Wu