Abstract:

Nano zero-valent iron (nZVI) has strong reduction and adsorption capacity, and can effectively remove various types of pollutants. It has been paid much attention in the field of groundwater environmental remediation. However, due to its defects of easy agglomeration and passivation, there are still many problems in practical application. In this paper, different preparation and modification methods of nZVI were reviewed. The specific effects and problems that may occur in the properties of nZVI-based composites due to their modification were identified. Recent research progress of nZVI particles for groundwater remediation including organic and inorganic pollutions was also introduced, focusing on the removal mechanism, mobility and transport in porous media. It is suggested that the existing preparation methods should be improved and optimized to realize the mass production of nZVI, considering the biological toxicity of nZVI and material recycling. Appropriate modification and transport means of nZVI should be considered to improve the life-span of nZVI and the treatment effects on the target pollutants in the remediation of groundwater.

Key words: nano zero-valent iron, nanomaterials, modification, groundwater pollution, environmental remediation

摘要：

纳米零价铁（nZVI）具有较强的还原和吸附能力，能有效去除多种类型的污染物质，在地下水环境修复领域一直备受关注。但由于其易团聚和易钝化等缺陷，在实际应用过程中还存在着许多问题。本文综述了nZVI的常用制备方法，并对nZVI的常用改性方法进行归纳，分析各种改性方法起到的具体作用，指出改性过后的复合材料依然存在着的问题。在此基础上，阐述了改性nZVI在去除地下水中有机污染物和无机污染物的应用进展，总结了改性nZVI材料在去除过程中起到的具体作用和反应机制，并进一步归纳现阶段nZVI在地下水修复中的传输手段。根据已有研究成果，指出应改进现有制备方法实现nZVI的量产，在考虑nZVI生物毒性和材料再回收的前提下，合理使用多种改性方式实现nZVI的材料制备，选择符合污染场地实际情况的传输手段，从而提高nZVI在地下水污染修复中的使用寿命和对目标污染物的处理效果。

关键词: 纳米零价铁, 纳米材料, 改性, 地下水污染, 环境修复