Electricity-Driven Microbial Metabolism of Carbon and Nitrogen: A Waste-to-Resource Solution

Abstract

Electricity-driven microbial metabolism relies on the extracellular electron transfer (EET) process between microbes and electrodes and provides promise for resource recovery from wastewater and industrial discharges. Over the past decades, tremendous efforts have been dedicated to designing electrocatalysts and microbes, as well as hybrid systems to push this approach toward industrial adoption. This paper summarizes these advances in order to facilitate a better understanding of electricity-driven microbial metabolism as a sustainable waste-to-resource solution. Quantitative comparisons of microbial electrosynthesis and abiotic electrosynthesis are made, and the strategy of electrocatalyst-assisted microbial electrosynthesis is critically discussed. Nitrogen recovery processes including microbial electrochemical N 2 fixation, electrocatalytic N 2 reduction, dissimilatory nitrate reduction to ammonium (DNRA), and abiotic electrochemical nitrate reduction to ammonia (Abio-NRA) are systematically reviewed. Furthermore, the synchronous metabolism of carbon and nitrogen using hybrid inorganic-biological systems is discussed, including advanced physicochemical, microbial, and electrochemical characterizations involved in this field. Finally, perspectives for future trends are presented. The paper provides valuable insights on the potential contribution of electricity-driven microbial valorization of waste carbon and nitrogen toward a green and sustainable society.

Super‐fast Charging Biohybrid Batteries through a Power‐to‐formate‐to‐bioelectricity Process by Combining Microbial Electrochemistry and CO2 Electrolysis

“…The stability of CO 2 RR presents a systematic challenge, which can be attributed to three main factors: [25] (a) an increase in resistance as the pH value of the KOH solution decreases; [23] (b) changes in the microenvironment due to flooding and salt accumulation, leading to blockage of mass transfer channels; [25–26] and (c) direct degradation of the electrocatalyst [27] . It is worth noting that the majority of studies on CO 2 RR have reported stability tests spanned only a couple of hours [7a] . Additionally, it has been observed that direct exposure of the GDE to a KOH solution could stimulate salt accumulation, compared to a neutral electrolyte [28] …”

Enhancing Predictions of Acetate and Ethanol Production from Microbial Electrosynthesis Using Optimized Machine Learning Models

“…Furthermore, electron availability, which is associated with the current, directly influences microbial electron utilization. Optimal electron availability enables microorganisms to fully exploit electrons for IC fixation, 52 while inadequate current restricts electron utilization, thereby reducing the conversion of IC to ethanol. Hence, the considerable importance assigned to these features is reasonable.…”

Electrochemical Nitrate Reduction: Ammonia Synthesis and the Beyond

“…In addition, microbial electrosynthesis holds higher potential in making multicarbon products with higher FE and better stability of over 300 days, and bio-electrochemical process will probably be the answer to industrial synthesis for green chemical vectors. [326,327] By changing the anodic reaction during nitrate reduction, different functions can be achieved. Chlorine oxidation reaction can assist the denitrification process, [328] and zinc anode can establish an energy output system with NO 3 RR.…”