摘要
电容法脱盐技术是以直流电为驱动力,利用电化学双电层充电原理脱盐的方法。本文利用恒压充放电方法,对装置的运行工艺,如施加电压、原水浓度和流速等因素对活性炭电极电吸附容量的影响进行了探讨;同时,对比研究了碱金属和碱土金属氯化物在活性炭电极表面的等电势吸附等温线的差异。结果表明,随施加电压提高,可以提高单位质量活性炭对离子的吸附容量,且0.6～1.5V范围内,吸附容量与施加电压呈线性增加关系。碱金属和碱土金属离子在活性炭电极表面的平衡吸附容量主要受其水化离子半径影响,即水化离子半径小,所带电荷少的阳离子吸附性能更好,依次为K+>Na+>Li+>Ca2+>Mg2+。
Capacitive desalination fechnology which using a DC power supply and electrostatic charge of electrochemical double layer for ions removing is a promising technology for desalting application. The parameters of desalination technique （such as voltages, flow velocity and concentration of electrolytes） and properties of activated carbon electrodes were studied by galvanostatic charge/discharge technologies. And the equipotential isotherm difference between alkali and alkaline earth metal chlorides on the activated carbon electrodes were compared. We found that the property of activated carbon electrodes for ions removing which depend on the voltage and flow velocity of solution, and appropriately higher voltage resulted in more adsorption amount. Adsorption amount of alkali and alkaline earth metal chlorides which fitted from Freundlich and Langmuir- Freundlich isotherm correlated with interaction between the ions and solvent.The order for adsorption of alkali and alkali earth metal chlovides is： K^＋〉Na^＋〉Ca^2＋〉Mg^2＋.
出处
《水处理技术》
CAS
CSCD
北大核心
2008年第3期31-34,共4页
Technology of Water Treatment
关键词
电吸附
离子半径
等电势吸附等温线
吸附容量
electrostatic adsorption, ion radii
equipotential isotherm
adsorption amount
