Microbial electrochemical technologies(MET)can remove a variety of organic and inorganic pollutants from contaminated groundwater.However,despite significant laboratory-scale successes over the past decade,field-scale...Microbial electrochemical technologies(MET)can remove a variety of organic and inorganic pollutants from contaminated groundwater.However,despite significant laboratory-scale successes over the past decade,field-scale applications remain limited.We hypothesize that enhancing the electrochemical conductivity of the soil surrounding electrodes could be a groundbreaking and cost-effective alternative to deploying numerous high-surface-area electrodes in short distances.This could be achieved by injecting environmentally safe iron-or carbon-based conductive(nano)particles into the aquifer.Upon transport and deposition onto soil grains,these particles create an electrically conductive zone that can be exploited to control and fine-tune the delivery of electron donors or acceptors over large distances,thereby driving the process more efficiently.Beyond extending the radius of influence of electrodes,these diffuse electro-conductive zones(DECZ)could also promote the development of syntrophic anaerobic communities that degrade contaminants via direct interspecies electron transfer(DIET).In this review,we present the state-of-the-art in applying conductive materials for MET and DIET-based applications.We also provide a comprehensive overview of the physicochemical properties of candidate electrochemically conductive materials and related injection strategies suitable for field-scale implementation.Finally,we illustrate and critically discuss current and prospective electrochemical and geophysical methods for measuring soil electronic conductivitydboth in the laboratory and in the fielddbefore and after injection practices,which are crucial for determining the extent of DECZ.This review article provides critical information for a robust design and in situ implementation of groundwater electro-bioremediation processes.展开更多
基金support under the National Recovery and Resilience Plan(NRRP)Mission 4,Component 2,Investment 1.1,Call for tender No.104 published on February 2,2022 by the Italian Ministry of University and Research(MUR)+2 种基金funded by the European Union e Next GenerationEUe Project Title SteeRing GroundwatEr Electro-bioremediAtion with ConducTIVe ParticlEs(REACTIVE)e CUP:B53D23018110006-Grant Assignment Decree No.1048 adopted on July 14,2023 by the Italian Ministry of University and Research(MUR).UM acknowledges Villum Foundation(grant n.VIL50414)the Grundfos Foundation(grant n.2017-025)LP and GC acknowledge The Geosciences for Sustainable Development project(Budget Ministero dell'Universita e della Ricerca-Dipartimenti di Eccellenza 2023-2027,C93C23002690001).
文摘Microbial electrochemical technologies(MET)can remove a variety of organic and inorganic pollutants from contaminated groundwater.However,despite significant laboratory-scale successes over the past decade,field-scale applications remain limited.We hypothesize that enhancing the electrochemical conductivity of the soil surrounding electrodes could be a groundbreaking and cost-effective alternative to deploying numerous high-surface-area electrodes in short distances.This could be achieved by injecting environmentally safe iron-or carbon-based conductive(nano)particles into the aquifer.Upon transport and deposition onto soil grains,these particles create an electrically conductive zone that can be exploited to control and fine-tune the delivery of electron donors or acceptors over large distances,thereby driving the process more efficiently.Beyond extending the radius of influence of electrodes,these diffuse electro-conductive zones(DECZ)could also promote the development of syntrophic anaerobic communities that degrade contaminants via direct interspecies electron transfer(DIET).In this review,we present the state-of-the-art in applying conductive materials for MET and DIET-based applications.We also provide a comprehensive overview of the physicochemical properties of candidate electrochemically conductive materials and related injection strategies suitable for field-scale implementation.Finally,we illustrate and critically discuss current and prospective electrochemical and geophysical methods for measuring soil electronic conductivitydboth in the laboratory and in the fielddbefore and after injection practices,which are crucial for determining the extent of DECZ.This review article provides critical information for a robust design and in situ implementation of groundwater electro-bioremediation processes.