摘要：本文简要介绍了纳米颗粒的基本性质以及纳米零价铁颗粒的制备和表征。纳米铁颗粒体积小，比表面积大，具有优越的吸附性能；同时零价铁的电负性较大，很容易作为还原剂被氧化为Fe2+，在一定条件下还可以继续被氧化为Fe3+，因此是一种化学还原性很强的还原剂，利用它来还原降解水体中的某些有机污染物，同时还可以起到催化剂的作用，加速反应过程。因此纳米零价铁颗粒在有机氯废水处理方面应用广泛。
本文应用改进液相还原法制备了纳米零价铁，并采取正交实验法研究了反应时间、反应介质与水的配比以及表面活性剂的用量3个因素对合成纳米零价铁的影响。在此基础上进一步制备了纳米级Pd/Fe双金属催化剂。通过透射电子显微镜(TEM)、X-射线衍射光谱(XRD)等分析检测手段，表征了纳米铁和纳米Pd/Fe双金属催化剂颗粒的形状、大小以及晶体结构。结果表明，合成的纳米铁颗粒分散性好，粒径较小且均匀；对于合成的纳米Pd/Fe双金属颗粒，钯均匀地负载在纳米铁球形颗粒表面。
关键词：纳米零价铁 制备 液相还原法 纳米Pd/Fe双金属催化剂
Abstract:In this paper, we have a brief introduction of the fundamental nature of zero-valent iron nanoparticles. Preparation and Characterization of zero-valent iron nanoparticles.
Nano-iron particles have superior absorption properties, due to its small volume and specific surface area; meanwhile zero-valent iron is more negative and as a reducing agent is easy to oxidation of Fe2 +, so it is a strong chemical reduction of the reducing agent. Using it to treatment organic pollutants in water, it can also play the role of catalyst to accelerate the reaction process. Therefore zero-valent iron nano-particles are widely applied in organic chlorine wastewater treatment applications.
In this study, the methods of modified liquid phase reduction are employed to prepare the nanoscale zero valent iron, and the orthogonal experimental method is taken to study the impact of the reaction time, the ratio of reaction medium and water, and the amount of surfactant on synthesizing nanoscale zero-valent iron. In addition, the nano-scale Pd/Fe bimetallic catalyst is synthesized. Through transmission electronic microscopy (TEM), X-ray diffraction (XRD) and other analytical methods, the shape, size and crystal structure of the nano iron and nano Pd/Fe bimetallic catalyst can be characterized.
Keywords: Nanoscale zero-valent iron ,preparation ,liquid phase reduction method , nano Pd/Fe bimetallic catalyst
