Efficient regeneration of activated carbon electrode by half-wave rectified alternating fields in capacitive deionization system
Efficient regeneration of activated carbon electrode by half-wave rectified alternating fields in capacitive deionization system
复制标题
电容去离子系统半波整流交变场高效再生活性炭电极
DOI：
10.1016/j.electacta.2018.12.098
复制
发表时间：
2019
影响因子：
6.6
通讯作者：
Wang X.
中科院分区：
文献类型：
--
作者：
Zhou L.;Li T.;An J.;Liao C.;Li N.;Wang X.
Capacitive deionization (CDI) is a promising technology for water desalination. An excellent desorption rate guarantees re-adsorption performance of CDI electrode in the following cycles. In this paper, we reported for the first time that the use of half-wave rectified alternating current (HWAC), a periodically changing electric field, improved electrodesorption in CDIs. Up to 90% of adsorbed NaCl can be released from activated carbon electrodes after HWAC (1.2 V, 1 kHz, 90 min) than 78% of direct current (DC, 1.2 V) powered systems, corresponding to a 79% current efficiency than 71% of DC. This was attributed to the elimination of capacitance in pores as well as the agitation of ions by the periodically changing electric field. Energy consumption per unit charge release decreased by 68% from 145 ± 11 J/(mmol e−) of DC to 46 ± 3 J/(mmol e−) of HWAC. Electrodesorption of MgSO4and the mixture of NaCl/MgSO4have similar results, indicating that the energy-saving strategy of HWAC was not affected by ionic charge or radius. These findings demonstrated that HWAC was a highly efficient waveform for maximizing the ion desorption from porous electrodes with a low energy requirement.
