Bioelectrochemical Remediation for the Removal of Petroleum Hydrocarbon Contaminants in Soil

Abstract

Consistent accumulation of petroleum hydrocarbon (PH) in soil and sediments is a big concern and, thus, warrants a static technology to continuously remediate PH-contaminated soil. Bioelectrochemical systems (BESs) can offer the desired solution using the inimitable metabolic response of electroactive microbes without involving a physiochemical process. To date, a wide range of BES-based applications for PH bioremediations under different environmental conditions is readily available in the literature. Here, the latest development trend in BESs for PH bioremediation is critically analyzed and discussed. The reactor design and operational factors that affect the performance of BESs and their strategic manipulations such as designing novel reactors to improve anodic reactions, enhancing soil physiology (electrical conductivity, mass diffusion, hydraulic conductivity), electrode modifications, operational conditions, microbial communities, etc., are elaborated to fortify the understanding of this technology for future research. Most of the literature noticed that a low mass diffusion condition in soil restricts the microbes from interacting with the contaminant farther to the electrodes. Therefore, more research efforts are warranted, mainly to optimize soil parameters by specific amendments, electrode modifications, optimizing experimental parameters, integrating different technologies, and conducting life cycle and life cycle cost analysis to make this technology viable for field-scale applications.

Ammonia Removal by Simultaneous Nitrification and Denitrification in a Single Dual-Chamber Microbial Electrolysis Cell

“…Autotrophic denitrification is advantageous due to the independence of the organic carbon requirement for nitrogen reduction and the low biomass generation [15]. In particular, the autotrophic bacteria accept the electron from a poised cathode either via the mediated transfer (by H 2 and enzymes) or via the direct electron transfer mechanism as discussed in the literature [16][17][18][19]. Overall, the operation of biocathode in BES for denitrification is sustainable for field-scale applications.…”