活性炭催化臭氧化处理含氰废水的试验研究

摘要

The degradation of low consistency cyanide wastewater with activated carbon catalytic ozonation is studied. The influences of ozone dosage, activated carbon dosage and initial pH on degradation effects are studied. Experiments indicate that activated carbon can not only accelerate the process of ozonation, but also enhance the utilization of ozone. With an initial CN - concentration of 150 mg/L, 30 mg/min of ozone dosage, and 14 g/L of activated carbon, the removal rate for CN- is 99.8 ％ for 30 min'reaction. Comparing to single ozonation, the removal rate of CN- is enhanced obviously. Hydroxyl radical is produced with the presence .of activated carbon, which is deduced from the effect of Na2CO3 on the reaction of catalytic activity. The adsorbent capabilities of activated carbon in the process of catalytic ozonation are also found. It is proved that the CN- removal process by catalytic ozonation is the homo-result of ozone direct oxidization, activated carbon adsorption and indirect oxidization of hydroxyl radical.%研究了活性炭催化臭氧化降解低质量浓度含氰废水,考察了臭氧投加量、活性炭用量、pH值等因素对处理效果的影响.试验结果表明:活性炭对臭氧有明显的催化作用,并可以提高臭氧的利用率;在CN-初始质量浓度150 mg/L、臭氧投加量30 mg/min、活性炭14 g/L、反应30 min条件下,CN-去除率为99.8%,相对于单独臭氧化过程CN-去除率有了显著提高;通过自由基捕捉剂Na2CO3对催化反应的影响,验证了活性炭催化臭氧化过程产生·OH;同时,还发现了催化臭氧化过程中活性炭的吸附效果;说明催化臭氧化去除CN-的过程为O3直接氧化、活性炭吸附与·OH间接氧化共同的结果.