污泥-秸秆基活性炭的制备及其对渗滤液COD的吸附

以市政污泥与玉米秸秆为原料,采用化学活化法热解制备污泥-秸秆基活性炭,研究其物化性质、热解动力学特性及对渗滤液中COD的吸附性能。考察吸附剂投加量、吸附时间和溶液pH对COD去除率的影响,并用吸附等温线对吸附数据进行了拟合。结果表明,秸秆比例越高,活性炭的吸附碘值和BET比表面积越大,最大可达663 mg/g和902 m2/g;活性炭表面呈不规则的多孔状;秸秆比例为45%的活性炭在最佳实验条件下对COD的吸附去除率为82%;活性炭对COD的吸附符合Langmuir和Freundlich等温模型。

Preparation of sludge-stalk based activated carbon and its adsorption of COD in leachate

Municipal sludge and corn stalk were used to prepare sludge-stalk based activated carbon by pyrolysis with chemical methods.The physical and chemical properties,pyrolytic kinetic characteristic and adsorption characteristics of COD in leachate were studied.The effects of adsorbent dosage,adsorption time and solution pH on COD removal were discussed and the adsorption isotherms were fitted.The results showed that the higher the proportion of stalk in activated carbon,the greater the iodine value and the BET surface area,which can up to 663 mg/g and 902 m2/g;the surface of carbon was irregular and porous;the COD removal rate of activated carbon with 45% stalk added was 82%.The adsorption experimental data were fitted by both Langmuir and Freundlich isotherm models.