Implementation of a Sulfide–Air Fuel Cell Coupled to a Sulfate-Reducing Biocathode for Elemental Sulfur Recovery

Abstract

Bio-electrochemical systems (BES) are a flexible biotechnological platform that can be employed to treat several types of wastewaters and recover valuable products concomitantly. Sulfate-rich wastewaters usually lack an electron donor; for this reason, implementing BES to treat the sulfate and the possibility of recovering the elemental sulfur (S0) offers a solution to this kind of wastewater. This study proposes a novel BES configuration that combines bio-electrochemical sulfate reduction in a biocathode with a sulfide–air fuel cell (FC) to recover S0. The proposed system achieved high elemental sulfur production rates (up to 386 mg S0-S L−1 d−1) with 65% of the sulfate removed recovered as S0 and a 12% lower energy consumption per kg of S0 produced (16.50 ± 0.19 kWh kg−1 S0-S) than a conventional electrochemical S0 recovery system.

Microbial Fuel Cell Using a Novel Ionic Liquid-Type Membrane–Cathode Assembly for Animal Slurry Treatment and Fertilizer Production

“…The research in this area in recent years has focused on the development of new nanostructured chemical catalysts, which are comparable with platinum in terms of reaction velocity, by using low-cost catalysts based on non-noble metals, in the hope of developing technologies that can be industrially implemented. Specifically, the catalysts described below were developed and tested in MFCs: (i) iron streptomycin [9], (ii) MnO 2 [10,11], (iii) iron aminoantipyrine [12], (iv) ferroelectric materials such as LiTaO 3 [13], (v) activated carbon [14], and (vi) biocathodes [15][16][17].…”