构造了简易的电容去离子(CDI)反应装置,以活性炭粉末为吸附材料,聚偏氟乙烯(PVDF)为黏结剂,石墨粉为导电剂。这3种物质的质量比为8∶1∶1。采用涂覆分解法制备活性炭电极,研究其电吸附除盐性能。利用扫描电子显微镜(SEM)对电极的表观形态进行分析,利用电化学工作站对电极材料的电化学性能进行分析,并估算单位质量电极的电容。通过单因素试验得到电容去离子试验的最佳反应条件:端电压为1.6 V,流量为10 L/min,极板间距为2 mm。此条件下离子去除率可达47.9%。吸附达平衡后断开电源,进行电极可再生性研究。结果表明,电极在短时间内即可再生。
The present paper would like to introduce a renovated electro-absorptive desalination method by using activated carbon coating electrodes.Since it is of great importance to remove ion from aqueous solutions both in natural environment and in industrial processes,for example,the desalination of seawater,there has been existing a promising method commonly known as capacitive deionization(CDI) for saline ion removal.It is just for satisfying such a need,we have developed a simplistic CDI cell reactor which we name flowing-through-capacitor(FTC) to study the mechanism of the electrosorptive desalination.In our work,we have prepared some activated carbon-coating electrodes in a simple and economic manner by coating a slurry mixture made of activated carbon powder(ACP) in a polymer solution including binder poly vinylidene fluoride(PVDF) and conductive graphite powder dissolved in di-methylacetamide(DMAc) on the current collector(a graphite plate).And,then,the mixture and the electric current collector were let to dry at 60 in a vacuum stove,in which the electrodes could be made to turn into activated carbon powder with a ratio of PVDF: graphite powder in 8:1:1.The electrodes here prepared can be characterized by using Scanning Electronic Microscopy(SEM) and Electrochemical workstation to analyze their surface morphology and electrochemical performance.The results of the SEM indicate that the activated carbon powder and PVDF binders tend to be effectively bonded.Measuring the cyclic voltammetry(CV) through a three-electrode-system in the CHI660 electrochemical workstation,we can obtain the specific capacitance from CV was 59.2 F/g.And,as a result,we can find that the influential factors of the electrodes chosen may have bias potential with their flowing rate and the distance between them.The best reaction conditions obtained by optimizing the affecting factors can be shown as follows: the bias potential was 1.6 V,the flowing rate was 10 L/min,the distance between the two electrod