| Water is the source of life and also the basic material guarantee for humanexistence and social development. At present, the shortage of freshwater becomes themain factor which restricts the development of society. Desalination as one of the mostimportant methods for water treatment, with its application, the supply and demandcontradiction of fresh water can be relieved at certain degree. High energy consumption,high cost and also the difficulty for regeneration make the application of traditionaldesalination suffer. Electrosorb Technology is a newly established treatment fordesalination which combined with electrochemical theory and Adsorption separationtechnology, with its advantages in energy efficiency, scaling prevention, convenientregeneration and no secondary pollution; it can be counts for a broad prospects forfurther development.In this article, the self designed activated carbon fiber electrode eclectic adsorptiondesalination plant was used to study with the influencing factors of desalinationefficiency during electro adsorption by the means of single factor analysis. Through theabove analysis, the most reasonable electrode logarithmic, electrode separation, voltage,flow velocity and the concentration can be determined. The removal performance ofvarious ions using the ACF electrode electric adsorption was analyzed here as well as apreliminary explore for enhancing the desalination efficiency for ACF electrode electricadsorption. The main results are as following:（1）Study on the influencing factors: The impact of electrode, voltage, flow rateand also the concentration on ACF electrode electric adsorption were analyzed respectively. The results show: at the specific range, with the increasing of electrodelogarithmic, the electrode spacing decreases, and as the voltage increases, the currentdecreases, which altogether enable higher desalination efficiency for electro adsorption.The most reasonable parameters were determined as:10for electrode logarithmic,5mmfor electrode spacing,2.0V for voltage,25ml/min for flow rate,600μs/cm for theconcentration, and the desalination efficiency for electrode adsorption could reach50%.（2）An entire process of electric adsorption desorption was analyzed to find outthe changing characteristic of water conductivity with the time were measured. With3periods of continuous operation of electric adsorption–desorption, the good electroderegeneration performance can be proved, furthering demonstrates its good cyclical andindustrial feasibility.（3）The adsorption laws for cation and anion were analyzed respectively duringthe process of electric adsorption. It can be found that the ion removal laws are the samein essence, which is to say during ion adsorption, with constant conditions, the removalvelocity and ratio of ions are inversely linked to its mass to charge ratio and itshydrated ionic radius respectively. Besides, the removal of heavy metal ions wasstudied here at the condition of ACF electric adsorption. The experiment result shows,through electric adsorption, heavy metal ions can be removed efficiently as well and theelectrode can be regenerated either.（4）In order to further improve the ion adsorption velocity for electric adsorption,Nitric acid, hydrogen peroxide and potassium hydroxide were used to process withACF respectively. After the process, the desalination efficiency shows different degreesof improvement. The results show, the optimal desalination effect can be achieved whenbeen soaked with3mol/L KOH at room temperature for24h, the desalination efficiencycan be as high as75%. After a further study on ACF electrode treated with KOH, itsadvantages in periodicity as well the regeneration can be proved. The SEM photos alsoshow, after treated by KOH, the ACF fiber becomes thinner with closely packed andbetter hydrophilia. |
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