活性焦吸附处理一硝基甲苯(MNT)废水

一硝基甲苯(MNT)废水是一种具有高毒性、难降解的火炸药废水。以活性焦为吸附剂,研究了活性焦对MNT废水中COD的吸附性能及pH、时间、温度和活性焦用量对吸附效果的影响,并分析了吸附前后MNT废水水质和急性毒性的变化。实验结果表明,pH、时间和活性焦用量是影响吸附效果的主要因素,吸附过程符合拟二级动力学,吸附速率常数为1.01×10-2g/(mg·min),可以用Freundlich吸附等温线来描述,等温线常数为Kf=1.14×10-4,n=0.58;在pH为3,温度为20℃,活性焦用量为80g/L的条件下吸附MNT废水3 h,COD的去除率达到72.0%,急性毒性下降了98.6%,表明活性焦能有效地吸附处理MNT废水。

Adsorption of mononitrotoluene(MNT) wastewater on active coke

Mononitrotoluene(MNT) wastewater is highly toxic and poorly degradable,which is generated from MNT production.In this study,active coke was used to reduce COD from MNT wastewater.The effects of pH,time,temperature and active coke dosage on COD removal were studied.The results showed that pH,time and active coke dosage were the dominant factors on COD removal.Under the conditions of pH =3,the temperature of 20°C,active coke dosage of 80 g/L and absorbing time of 3 h,72.0% of COD in MNT wastewater was removed,and the acute toxicity was reduced by 98.6%.The adsorption kinetics of COD removal on active coke was coincident with pseudo second-order model and the rate constant was 1.01×10^-2 g/(mg(min); the adsorption isotherm was in good agreement with Freundlich isotherm and the Freundlich constants were Kf=1.14×10^-4,n=0.58.These results indicated that active coke was indeed an efficient absorbent for MNT wastewater treatment.