title: An overview of preparation and applications of stabilized zero-valent iron nanoparticles for soil and groundwater remediation.
abstract: Nano-scale zero-valent iron (nZVI) is one of the most intensively studied materials for environmental cleanup uses over the past 20 years or so. Freshly prepared nZVI is highly reactive due to its high specific surface area and strong reducing power. Over years, the classic borohydride reduction method for preparing nZVI has been modified by use of various stabilizers or surface modifiers to acquire more stable and soil deliverable nZVI for treatment of different organic and inorganic contaminants in water and soil. While most studies have been focused on testing nZVI for water treatment, the greater potential or advantage of nZVI appears to be for in situ remediation of contaminated soil and groundwater by directly delivering stabilized nZVI into the contaminated subsurface as it was proposed from the beginning. Compared to conventional remediation practices, the in situ remediation technique using stabilized nZVI offers some unique advantages. This work provides an update on the latest development of stabilized nZVI for various environmental cleanup uses, and overviews the evolution and environmental applications of stabilized nZVI. Commonly used stabilizers are compared and the stabilizing mechanisms are discussed. The effectiveness and constraints of the nZVI-based in situ remediation technology are summarized. This review also reveals some critical knowledge gaps and research needs, such as interactions between delivered nZVI and the local biogeochemical conditions.
authors.affiliation: Environmental Engineering Program, Department of Civil Engineering, Auburn University, Auburn, AL 36849, USA.
authors.forename: Xiao
authors.initials: X
authors.lastname: Zhao
authors.affiliation: Environmental Engineering Program, Department of Civil Engineering, Auburn University, Auburn, AL 36849, USA.
authors.forename: Wen
authors.initials: W
authors.lastname: Liu
authors.affiliation: Environmental Engineering Program, Department of Civil Engineering, Auburn University, Auburn, AL 36849, USA.
authors.forename: Zhengqing
authors.initials: Z
authors.lastname: Cai
authors.affiliation: Environmental Engineering Program, Department of Civil Engineering, Auburn University, Auburn, AL 36849, USA.
authors.forename: Bing
authors.initials: B
authors.lastname: Han
authors.affiliation: Institute of Environmental Science, Taiyuan University of Science and Technology, Taiyuan, Shanxi 030024, PR China.
authors.forename: Tianwei
authors.initials: T
authors.lastname: Qian
authors.affiliation: Environmental Engineering Program, Department of Civil Engineering, Auburn University, Auburn, AL 36849, USA; Institute of Environmental Science, Taiyuan University of Science and Technology, Taiyuan, Shanxi 030024, PR China. Electronic address: zhaodon@auburn.edu.
authors.forename: Dongye
authors.initials: D
authors.lastname: Zhao
mesh_terms: D052918:Environmental Restoration and Remediation; D060587:Groundwater; D007501:Iron; D053768:Metal Nanoparticles; D012987:Soil
chemical_list: D012987:Soil; D007501:Iron
keywords: Dechlorination; Groundwater; Soil remediation; Stabilized nanoparticles; Water contamination; Zero-valent iron