Preparation of functionalized Pd/Fe-Fe3O4@MWCNTs nanomaterials for aqueous 2,4-dichlorophenol removal: Interactions, influence factors, and kinetics.
Preparation of functionalized Pd/Fe-Fe3O4@MWCNTs nanomaterials for aqueous 2,4-dichlorophenol removal: Interactions, influence factors, and kinetics.
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DOI：
10.1016/j.jhazmat.2016.04.063
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发表时间：
2016-11
影响因子：
13.6
通讯作者：
Jiang Xu;Z. Cao;Xue Liu;Heng Zhao;Xi Xiao;Jiaping Wu;Xinhua Xu;John L. Zhou
中科院分区：
文献类型：
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作者：
Jiang Xu;Z. Cao;Xue Liu;Heng Zhao;Xi Xiao;Jiaping Wu;Xinhua Xu;John L. Zhou
制备了磁性多壁碳纳米管（MWCNTs），用于负载Pd/Fe纳米粒子，抑制团聚和钝化，实现磁性分离，避免纳米粒子的环境风险。初始污染物的快速吸附，稳定的脱氯，和最终产物的逐渐解吸。采用EDX、XRD、SEM、TEM、XPS等分析技术对纳米杂化材料的微观形貌、化学结构和组成进行了全面表征。根据表征和实验数据讨论了纳米杂化物组分之间的相互作用。对2，4-二氯苯酚（2，4-DCP）的吸附-脱氯-脱附过程进行了详细的研究，包括脱氯途径、影响因素、脱氯动力学和脱氯选择性。弱酸性（pH = 5.0和6.5）有利于2，4-DCP的去除。在连续5次运行中观察到令人满意的Pd/Fe-Fe 3 O 4 @MWCNTs纳米杂化物的反应性，2，4-DCP的去除率分别为99.2%、89.6%、92.1%、99.8%和99.9%。大部分最终产物（苯酚）被稳定地解吸到液相中，导致纳米杂化物上的活性位点重新暴露，并保持较长的活性。
Magnetic multi-walled carbon nanotubes (MWCNTs) were prepared to support Pd/Fe nanoparticles, inhibit the aggregation and passivation, and achieve magnetic separation to avoid the environmental risk of nanoparticles. Rapid adsorption of initial contaminant, steady dechlorination, and gradual desorption of final product was observed. The micromorphology, chemical structure, and components of the nanohybrids were comprehensively characterized by a series of analysis technologies, such as EDX, XRD, SEM, TEM, and XPS. The interactions between the nanohybrids compositions were discussed according to the characterization and experimental data. The whole insight of 2,4-dichlorophenol (2,4-DCP) adsorption- dechlorination-desorption was studied in detail, including the pathways, influence factors, dechlorination kinetics and selectivity. Weak acidity (pH = 5.0 and 6.5) favored the 2,4-DCP removal. Satisfactory reactivity of the Pd/Fe-Fe3O4@MWCNTs nanohybrids was observed in five consecutive runs, and 99.2%, 89.6%, 92.1%, 99.8%, and 99.9% of 2,4-DCP was removed, respectively. Most of the final product (phenol) was steadily desorbed to the liquid phase, resulted in the re-exposure of active sites on the nanohybrids and maintained a longer activity.