摘要
通过对5种不同活性炭的去除余氯量实验、余氯穿透实验以及化学反应产物Cl-的质量平衡数据,探讨了活性炭去除余氯的性能和机制。活性炭去除余氯是吸附与化学反应共同作用的结果。活性炭与水中余氯接触后的初期,去除余氯以吸附作用为主;达到吸附平衡后,余氯浓度继续下降则是由于化学反应的作用。接触时间越长、余氯初始浓度越高、pH较低,活性炭去除余氯量越大。由Cl-的生成量可以确定化学反应去除余氯量是余氯总去除量的一部分;接触时间越长,活性炭剂量越大,化学反应去除余氯量占余氯总去除量的比例越高。使用粒径<180目活性炭进行余氯去除实验,吸附容量在1～2h即达到饱和。活性炭对余氯吸附量(2h的余氯去除量)的大小与其苯酚值排行相同。苯酚值及碘值较高的煤质炭与余氯有较强的化学反应,果壳炭其次,而椰壳炭的化学性相对稳定。
A series of experiments were performed to compare the dechlorination effectiveness of 5 activated car bons in batch reactors by contact runs and carbon column breakthrough runs. The removal of free chlorine was accomplished by physical adsorption and chemical reaction; adsorption was the main removal mechanism initially while chemical reaction was responsible for continuing the removal of free chlorine after adsorption equilibrium had been established. Removal of free chlorine was enhanced by： a longer contact time,a higher initial/influent free chlorine concentration, and a lower pH. The release of chloride ions demonstrated the role of the chemical reaction that observed free chlorine removal. Using 〈 180 mesh particles of activated carbon in mixed batch reactors, the carbon＇s adsorptive capacity for free chlorine was established quickly （〈2 h） ; the carbons＇ capacities for free chlorine were in the same order as their phenol numbers. The coal based activated carbon with high phenol and iodine numbers was most reactive with free chlorine,followed by the fruit shell and coconut shell based carbons. Much more free chlorine was removed in both lab size and full size carbon columns based on the carbon＇s adsorptive capacity.
出处
《环境污染与防治》
CAS
CSCD
北大核心
2008年第5期63-68,共6页
Environmental Pollution & Control
关键词
活性炭
余氯
去除
物理吸附
化学反应
activated carbon
chlorine residual
removing
physical adsorption
chemical reaction
