次氯酸钠改性磁性碳纳米管吸附剂的制备及吸附性能研究  

STUDY ON THE PREPARATION AND ADSORPTION PROPERTIES OF MAGNETIC CARBON NANOTUBES MODIFIED BY NaClO

作　　者：虞琳琳[1] 马杰[1] 袁志文[1] 虞晓敏[1] 陈君红[1] 

机构地区：[1]同济大学污染控制与资源化研究国家重点实验室,上海200092

出　　处：《水处理技术》2011年第10期21-26,共6页Technology of Water Treatment

基　　金：国家自然科学基金(51072135);高等学校博士学科点专项科研基金(20100072110033);同济大学青年优秀人才培养行动计划(2010KJ026)

摘　　要：本文利用直接制备的碳纳米管原始样品作为偶氮染料的吸附剂,采用次氯酸钠溶液对碳纳米管进行表面修饰改性,改性后显著提高了吸附剂的吸附容量,本工艺简单有效,所获得的吸附剂具有磁性,吸附过后用磁铁易于达到固液分离的效果。吸附性能结果表明,次氯酸钠改性后碳纳米管对水中甲基橙去除效果明显高于未改性的碳纳米管。吸附剂对水中甲基橙的吸附在70 min基本达到平衡,吸附过程符合准2级动力学模型(R2>0.99)。改性后的磁性碳纳米管吸附甲基橙的平衡吸附量qe与甲基橙溶液的平衡浓度ρe的关系满足Langmuir(R2>0.99),Freundlich(R2>0.98)以及Dubinin-Radushkevich(D-R)(R2>0.99)等温吸附模型。通过Langmuir模型计算可知改性磁性碳纳米管最大吸附容量为29.2 mg.g-1,吸附过程为有利吸附,由D-R模型计算结果可以推断,次氯酸钠改性后的磁性碳纳米管对水溶液中甲基橙的吸附以物理吸附为主。In this paper, the adsorption of azo-dyes in water was investigated using as-synthesized magnetic carbon nanotubes （mCNTs） modified by NaCIO. In particular, the adsorption capacity of modified mCNTs for methyl orange was significantly higher than that of the pristine mCNTs. This method to remove methyl orange was simple and effective. The new adsorbent could be easily separated from aqueous solution after adsorption due to its magnetic properties. The adsorption of methyl orange reached equilibrium within 70 minutes of adsorption. Kinetic analyses were conducted using pseudo first- and second-order models and the intraparticle diffusion model. The regression results showed that the adsorption kinetics were more accurately represented by pseudo second-order model （R2〉0.99）. The equilibrium adsorption data were analyzed using three widely applied isotherms： Langmuii＇, Freundlich and Dubinin-Radushkevich （D-R）. The results suggested that all isotherm models can fit the experimental data reasonably well. Based on the Langmuir model, the maximum adsorption capacity of modified mCNTs was 29.2 mg .g 6-1, and the adsorption process was favored. The adsorption mechanism ofmCNTs modified by NaCIO on methyl orange was mainly attributed to the ohvsical adsomtion based on the D-R model.

关 键 词：磁性碳纳米管 次氯酸钠 吸附 甲基橙 

分 类 号：TQ424.2[化学工程] X788[环境科学与工程—环境工程]