木质素基活性炭对刚果红的吸附性能研究

Study on the adsorption characteristics of Congo red by lignin-based activated carbon

以纤维乙醇生产副产物木质素为原料,通过水蒸气活化方法制备木质素基活性炭。研究木质素基活性炭对刚果红(CR)废水的吸附行为,主要考察吸附时间、pH、吸附剂用量和温度等实验条件对吸附效果的影响。用Langmuir、Freundlich、Redlich-Peterson和Temkin等温模型,对木质素基活性炭吸附CR的吸附平衡数据进行拟合分析,结果表明,活性炭对刚果红的吸附过程符合Langmuir、Redlich-Peterson和Temkin等温吸附模型。动力学研究发现,吸附过程可以用准二级动力学模型很好的描述。活性炭对CR的吸附过程是一个以化学吸附为主的自发吸热过程。298 K时,最大饱和吸附量为0.089 7 mmol/g,木质素基活性炭对CR有良好的吸附性能,可用于CR废水处理用吸附剂。

The activated carbon achieved from the coproduct of cellulosic ethanol fermentation via steam activation was used to adsorb Congo red（ CR）. It has been investigated the influence of contact time,dosage of adsorbent and initial p H on the adsorption. The equilibrium data agreed well with the Langmuir,Freundlich,Redlich-Peterson and Temkin isotherm model. The dynamic data fitted the pseudo-second-order model well which suggested that the adsorption might be an endothermic process predominated by chemical adsorption. The maximum adsorption capacity of CR onto activated carbon was 0. 089 7 mmol / g,which shows that the activated carbon produced from the coproduct of cellulosic ethanol fermentation has a good adsorption of CR and can be used in sewage treatment.