Remediation of soil and groundwater contaminated with organic chemicals using stabilized nanoparticles: Lessons from the past two decades

Abstract

Due to improved soil deliverability and high reactivity, stabilized nanoparticles have been studied for nearly two decades for in situ remediation of soil and groundwater contaminated with organic pollutants. While large amounts of bench- and field-scale experimental data have demonstrated the potential of the innovative technology, extensive research results have also unveiled various merits and constraints associated different soil characteristics, types of nanoparticles and particle stabilization techniques. Overall, this work aims to critically overview the fundamental principles on particle stabilization, and the evolution and some recent developments of stabilized nanoparticles for degradation of organic contaminants in soil and groundwater. The specific objectives are to: 1) overview fundamental mechanisms in nanoparticle stabilization; 2) summarize key applications of stabilized nanoparticles for in situ remediation of soil and groundwater contaminated by legacy and emerging organic chemicals; 3) update the latest knowledge on the transport and fate of stabilized nanoparticles; 4) examine the merits and constraints of stabilized nanoparticles in environmental remediation applications; and 5) identify the knowledge gaps and future research needs pertaining to stabilized nanoparticles for remediation of contaminated soil and groundwater. Per instructions of this invited special issue, this review is focused on contributions from our group (one of the pioneers in the subject field), which, however, is supplemented by important relevant works by others. The knowledge gained is expected to further advance the science and technology in the environmental applications of stabilized nanoparticles.

Integration of microbial reductive dehalogenation with persulfate activation and oxidation (Bio-RD-PAO) for complete attenuation of organohalides

“…To remove organohalides from contaminated environments, many different remediation strategies have been developed, including both biotic and abiotic remediation methods: (1) physical strategies, e.g., high temperature and pressure, air sparging, electroremediation, active carbon adsorption and filtration (Ranck et al, 2005;Yang et al, 2005); (2) chemical methods, e.g., photocatalysis, metal catalysis, electrochemical catalysis and persulfate activation and oxidation (PAO) (Mascolo et al, 2008;Cai et al, 2020); and (3) biological techniques, e.g., phytoremediation and bioremediation (Wallace and Kadlec, 2005;Martinez et al, 2007). Almost all of the above-mentioned remediation methods can be conducted in situ and ex situ (pump-and-treat).…”

Degradation of tetrachloroethylene by zero valent iron nanoparticles in the presence of a natural groundwater bacterial biofilm in a sandy porous media

“…ZVI is commonly described as efficient in PRB as a reducing agent ( Obiri-Nyarko et al., 2014 ), although other materials have also been described for groundwater in situ remediation of various organic contaminants (halogenated or phenolic compounds, pharmaceuticals, nitroaromatics, etc. ( Cai et al., 2020 )), such as zeolite ( Vignola et al., 2011 ), calcite ( Turner et al., 2008 ), pyrite ( Wang et al., 2020 ) or combined materials ( Liu et al., 2019 ). Advantages of nanoparticles as a remediation agent are their high reactivity due to their higher specific surface area ( Cundy et al., 2008 ; Zhang, 2003 ) and their ability to be directly injected into the aquifer to treat both source and plume areas.…”

“…Advantages of nanoparticles as a remediation agent are their high reactivity due to their higher specific surface area ( Cundy et al., 2008 ; Zhang, 2003 ) and their ability to be directly injected into the aquifer to treat both source and plume areas. As for PRB, ZVI is often used in remediation using NPs, but other stabilized nanoparticles have been developed, such as Fe 3 O 4 , FeS, bimetallic Fe–Mn binary oxides or Fe 3 (PO 4 ) 2 ( Cai et al., 2020 ). Amongst the methods tested in the past decades ( Kim et al., 2017 ; Stroo et al., 2012 ), zero-valent iron (ZVI) injected as nanoparticles (nZVI) has be proven to be efficient for dechlorinating PCE through chemical reduction ( Dong et al., 2019 ; Fu et al., 2014 ; Gillham and O'Hannesin, 1994 ; Han et al., 2019 ; Henderson and Demond, 2007 ; Stefaniuk et al., 2016 ; Thiruvenkatachari et al., 2008 ).…”

Zero-Valent Iron Nanoparticles for Soil and Groundwater Remediation

“…On one hand, in situ soil treatment is a method in which the contaminated soil is treated without removing it. This method is especially interesting because it minimizes the alteration of characteristics such as soil structure and integrity [8,9]. However, this method, frequently, presents a lower remediation potential, being often considered time-consuming and presenting many uncertainties during the process.…”