改性碳纳米管负载Pd基催化剂对二氯乙酸的催化加氢脱氯  

Liquid phase catalytic hydrodechlorination of dichloroacetic acid over Pd catalysts supported on chitosan modified carbon nanotube

作　　者：周杨[1] 周娟[1] 万玉秋[1] 郑寿荣[1] 

机构地区：[1]污染控制与资源化研究国家重点实验室南京大学环境学院,南京210046

出　　处：《环境化学》2014年第3期515-521,共7页Environmental Chemistry

基　　金：国家自然科学基金(21277066)资助

摘　　要：以壳聚糖(chitosan,CS)为单体,采用表面沉积交联法对多壁碳纳米管(CNT)改性得到壳聚糖修饰的碳纳米管(CS-CNT).分别以CS-CNT和CNT为载体,用硼氢化钠还原法制备Pd/CNT和Pd/CS-CNT负载型催化剂.采用元素分析仪、电感耦合等离子体发射光谱仪(ICP)、透射电镜(TEM)、比表面积与孔径分布测定仪(BET)、X射线光电子能谱(XPS)等对材料进行表征,并对二氯乙酸的液相催化加氢脱氯反应进行了研究.结果表明,与Pd/CNT相比,Pd/CS-CNT对二氯乙酸有更高的催化活性.此外,该催化加氢脱氯反应受溶液pH及催化剂表面Pd颗粒的影响.二氯乙酸的催化加氢脱氯反应符合Langmuir-Hinshelwood模型,表明该反应过程由二氯乙酸在催化剂表面的吸附所控制.Carbon nanotube （denoted as CNT） was modified by chitosan via a controlled surface-deposition and crosslinking method （denoted as CS-CNT）, and supported Pd catalysts with CS-CNT and CNT as the supports were prepared by the reduction method with NaBH4. The catalysts were characterized by elemental analyzer, Inductive coupled plasma （ICP）, Transmission electron microscopy （TEM）, brunauer-Emmett-Teller （BET） and X-ray photoelectron spectroscopy （XPS）,respectively. The liquid phase catalytic hydrodechlorination of dichloroacetic acid over the catalysts was investigated. The results showed that compared with Pd/CNT, Pd/CS-CNT exhibited a higher catalytic activity for the catalytic hydrodechlorination of dichloroacetic acid. In addition, the catalytic hydrodechlorination was also influenced by the pH and palladium particles. The hydrodechlorination of dichloroacetic acid followed the Langumuir-Hinshelwood model, indicating that the hydrodechlorination was controlled by the adsorption of dichloroacetic acid on the catalyst surface.

关 键 词：PD CNT PD CS-CNT 碳纳米管改性 二氯乙酸 催化加氢脱氯 

分 类 号：TQ426[化学工程] X52[环境科学与工程—环境工程]