以钛基氧化物涂层材料(Ti/SnO2-Sb2O5-IrO2)为阳极,碳纳米管修饰的石墨(GE—CNT)为阴极构建电化学系统进行硝酸根(NO3-)去除研究,考察了阴极材料、阴极电位和pH值对电化学法去除水中NO[的影响,同时检测了铵离子(NH4+)和亚硝酸根(NO2-)的生成量。结果表明,利用碳纳米管修饰的石墨阴极可获得较好的硝态氮去除效果;随着阴极电位负移,NO3-去除率随之升高;酸性条件下NO3-去除率最高,NH;生成量也更多。对于由NO3-转化产生的NH4+,在氯离子存在条件下再次进行电化学处理120min,其去除率可达97.1%。
The removal of nitrate nitrogen was carried out by an electrochemical system using Ti/SnO2- SbEOs-IrO2 as anode and the graphite electrode coated with carbon nanotube (GE-CNT) as cathode. The influ- ences of cathode materials, cathodic potential, pH on the removal of nitrate nitrogen were investigated and NH~ generated by NO3- reduction was determined. The results show that using GE-CNT cathode can present a better removal of nitrate nitrogen. When cathodic potential became negative, the removal efficiency of nitrate nitrogen increased. The highest removal efficiency was obtained under acidic conditions accompanied with more ammonia nitrogen generating. The produced ammonia nitrogen from NO3- reduction can be removed by proceeding electro- chemical treatment in the presence of chloride ion and in this case, the removal rate of ammonia nitrogen reach to 97. 1% by the treatment of 120 min.