活性炭三维电极电促吸附去除水中氟离子的研究  

Studies on three-dimensional electrode of granular activated carbons on the removal of fluoride in drinking water

作　　者：杨硕[1] 梁文艳[1] 黎亮[1] 张嘉[2] 陈莉[1] 

机构地区：[1]北京林业大学环境科学与工程学院,北京100083 [2]中国科学院研究生院,北京100049

出　　处：《环境工程学报》2010年第7期1448-1452,共5页Chinese Journal of Environmental Engineering

基　　金：国家"863"高技术研究发展计划项目(2007AA06Z301);国家自然科学基金资助项目(50678024)

摘　　要：主要研究颗粒活性炭作为第三维电极电促吸附水中氟离子。通过在颗粒活性炭上施加不同电压,测定吸附容量和考察吸附动力学过程,结果表明,将电压控制在3~5 V范围内可有效增强三维电极的吸附容量,5 V电压下的电促吸附容量比开路电位下提高30%,同时此电促吸附反应符合一级反应动力学。在动态开放式实验中,所施加电压、含氟水样pH、电解质浓度、初始氟离子浓度和进水流量均对电促吸附容量产生影响。采用电子扫描电镜和氮气吸附脱附的方法比较吸附前后活性炭颗粒表面性质的变化,发现其表面并未发生氧化反应,孔容孔径也未发生明显变化,且孔径大小与电促吸附有一定的关联。综合这些实验结果表明,三维电极电促吸附可有效提高颗粒活性炭的吸附效果,这是由于活性炭电极表面产生双电层作用的结果,并非活性炭表面或者水溶液中产生氧化反应所至。Activated carbons as three-dimensional electrodes were prepared to adsorb fluoride in drinking water.The electrosorption capacity of activated carbon electrodes with different bias potentials were measured,and the electrosorption kinetics were also investigated.The results showed that electrosorption can effectively increase the adsorption capacity from 3 V to 5 V.With electrosorption of activated carbons from aqueous solution,a 30 percent enhancement of adsorption capacity was achieved at 5 V,compared with the adsorption capacity at 0 V.Meanwhile,the electrosorption of three-dimensional electrodes followed the first-order adsorption kinetics.The electrosorption capacity exhibits a variety of responses depending on bias potential,pH,electrolyte,fluoride concentration and flow rate.The initial and saturated activated carbons were characterized using scanning electron micrograph（SEM） and nitrogen adsorption.The SEM micrographs show that the surface of activated carbons are not oxidized.The nitrogen adsorption suggests that the average pore which interacts electroption has no significant change before and after adsorption.These experimental results suggest that the three-dimensional electrode can effectively improve the adsorption capacity of activated carbons,which may be due to they produce electric double layer capacitance instead of the oxidation on the surface of activated carbons or in the solution.

关 键 词：除氟 颗粒活性炭 三维电极 电促吸附 

分 类 号：X703.1[环境科学与工程—环境工程]