吴杰,张佩,吴纯鑫,赵德明.纳米级Pd/Fe-MWCNTs-Fe3O4体系对2,3-DCB的降解研究[J].环境科学学报,2019,39(5):1509-1518
纳米级Pd/Fe-MWCNTs-Fe3O4体系对2,3-DCB的降解研究
- Degradation of 2,3-dichlorobiphenyl by Pd/Fe-MWCNTs-Fe3O4 nanocomposites
- 基金项目：浙江省自然科学基金（No.LY19B070006）
- 吴杰
- 浙江工业大学化学工程学院, 杭州 310014
- 张佩
- 浙江工业大学化学工程学院, 杭州 310014
- 吴纯鑫
- 浙江工业大学化学工程学院, 杭州 310014
- 赵德明
- 浙江工业大学化学工程学院, 杭州 310014
- 摘要：为有效抑制纳米级Pd/Fe颗粒的团聚和钝化及改善磁分离效果，以多壁碳纳米管（MWCNTs）和磁性纳米级Fe3O4颗粒为载体，在超声波辐照下利用液相还原法制备纳米级Pd/Fe-MWCNTs-Fe3O4颗粒，并采用XRD、TEM、SEM、EDX及BET表征其物性，最后以2，3-二氯联苯（2，3-DCB）为目标污染物，探究其对2，3-DCB还原脱氯的影响因素、降解机理和动力学.结果表明：制备的纳米级颗粒粒径均匀、分散性好、比表面积大；体系中纳米级Pd/Fe投加量、钯化率、纳米级Fe3O4投加量、MWCNTs投加量、反应温度、溶液初始pH及共存阴离子均会对2，3-DCB的降解效果产生明显影响；本研究推测出纳米级Pd/Fe-MWCNTs-Fe3O4体系对2，3-DCB的降解机理，发现其降解符合拟一级动力学关系.
- Abstract：To inhibit the agglomeration and passivation of Pd/Fe nanoparticles and enable magnetic separation, multi-walled carbon nanotubes/magnetic Fe3O4 nanoparticles (MWCNTs-Fe3O4) composite was employed as platform to support them. Pd/Fe-MWCNTs-Fe3O4 nanocomposites were prepared via a facile liquid phase reductive method with the aid of ultrasound irradiation, and were full characterized by XRD, TEM, SEM, EDX, and BET. Thereafter, the catalytic performance of Pd/Fe-MWCNTs-Fe3O4 was checked using the model reaction of 2,3-dichlorobiphenyl (2,3-DCB) dechlorination, wherein the influential factors, degradation kinetics, and reaction mechanism were investigated. It can be found that:①the degradation of 2,3-DCB followed pseudo-first-order kinetics; ②the highly dispersed Pd/Fe nanoparticles with uniform size as well as large surface area of Pd/Fe-MWCNTs-Fe3O4 catalyst could be accounted for the superior activity of 2,3-DCB dechlorination; ③several factors such as Pd/Fe nanoparticles dosage, palladium content, Fe3O4 nanoparticles dosage, MWCNTs dosage, reaction temperature, initial pH and coexisting anions in the solution significantly affect the degradation of 2,3-DCB.
