Dechlorination Mechanism of 2,4-Dichlorophenol by Magnetic MWCNTs Supported Pd/Fe Nanohybrids: Rapid Adsorption, Gradual Dechlorination, and Desorption of Phenol

详细信息    查看全文

• 作者：Jiang Xu ; Xue Liu ; Gregory Victor Lowry ; Zhen Cao ; Heng Zhao ; John L. Zhou ; Xinhua Xu
• 刊名：ACS Applied Materials & Interfaces
• 出版年：2016
• 出版时间：March 23, 2016
• 年：2016
• 卷：8
• 期：11
• 页码：7333-7342
• 全文大小：733K
• ISSN：1944-8252

文摘

2,4-dichlorophenol was effectively removed from water using magnetic Pd/Fe nanoparticles supported on multiwalled carbon nanotubes (MWCNTs). The adsorption kinetics, isotherms, and energy for 2,4-dichlorophenol and its partially (4-chlorophenol, 2-chlorophenol) and completely (phenol) dechlorinated products are presented and discussed. The adsorption capacity was 2,4-dichlorophenol > 4-chlorophenol > 2-chlorophenol > phenol for MWCNTs. MWCNTs-Fe₃O₄–Pd/Fe nanohybrids provided rapid adsorption, gradual dechlorination, and final desorption of phenol, which is attractive as a remediation technology. Over 82.7% of the phenol was desorbed and released to the aqueous phase after 72 h due to its low adsorption capacity, leaving the majority of active sites available on the surface of MWCNTs-Fe₃O₄–Pd/Fe. The nanohybrids maintained high activity in five consecutive in situ experiments, and they were retrievable using magnetic separation. MWCNTs-Fe₃O₄–Pd/Fe nanohybrids outperform unsupported Pd/Fe nanoparticles, which were difficult to retrieve, and were easily passivated and aggregated.