School of Environmental Science and Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India.
Department of Civil Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India.
J Environ Manage. 2023 Apr 15;332:117323. doi: 10.1016/j.jenvman.2023.117323. Epub 2023 Jan 28.
Microbial electrosynthesis (MES) is a neoteric technology that facilitates biocatalysed synthesis of organic compounds with the aid of homoacetogenic bacteria, while feeding CO as an inorganic carbon source. Operating MES with surplus renewable electricity further enhances the sustainability of this innovative bioelectrochemical system (BES). However, several lacunae exist in the domain knowledge, stunting the widespread application of MES. Despite significant progress in this area over the past decade, the product yield efficiency is not on par with other contemporary technologies. This bottleneck can be overcome by adopting a holistic approach, i.e., applying innovative and integrated solutions to ensure a robust MES operation. Further, the widespread deployment of MES exclusively relies on its ability to mature a sessile biofilm over a biocompatible electrode, while offering minimal charge transfer resistance. Additionally, operating MES preferably at H-generating reduction potential and valorising industrial off-gas as carbon substrate is crucial to accomplish economic sustainability. In light of the aforementioned, this review collates the latest progress in the design and development of MES-centred systems for valorisation of CO into value-added products. Specifically, it highlights the significance of inoculum pre-treatment for promoting biocatalytic activity and biofilm growth on the cathodic surface. In addition, it summarizes the diverse materials that are commonly used as electrodes in MES, with an emphasis on the importance of inexpensive, robust, and biocompatible electrode materials for the practical application of MES technology. Further, the review presents insights into media conditions, operational factors, and reactor configurations that affect the overall performance of MES process. Finally, the product range of MES, downstream processing requirements, and integration of MES with other environmental remediation technologies are also discussed.
微生物电合成（MES）是一种新技术，它借助同型产乙酸菌，在以 CO 作为无机碳源的情况下，促进有机化合物的生物催化合成。利用剩余的可再生电力运行 MES 进一步提高了这种创新型生物电化学系统（BES）的可持续性。然而，该领域的知识存在一些空白，阻碍了 MES 的广泛应用。尽管在过去十年中，该领域取得了显著进展，但产品产率效率仍不及其他当代技术。可以通过采用整体方法来克服这一瓶颈，即应用创新和集成的解决方案，以确保 MES 的稳健运行。此外，MES 的广泛部署完全依赖于其在生物相容性电极上形成静止生物膜的能力，同时提供最小的电荷转移电阻。此外，在产生 H 的还原电位下运行 MES 并将工业废气作为碳源加以利用对于实现经济可持续性至关重要。有鉴于此，本综述汇集了最新的进展，设计和开发以 MES 为中心的系统，将 CO 转化为增值产品。具体来说，它强调了接种物预处理对于促进阴极表面的生物催化活性和生物膜生长的重要性。此外，它总结了常用于 MES 的各种材料，重点介绍了廉价、坚固和生物相容的电极材料对于 MES 技术实际应用的重要性。此外，该综述还介绍了影响 MES 过程整体性能的介质条件、操作因素和反应器配置。最后，还讨论了 MES 的产品范围、下游处理要求以及 MES 与其他环境修复技术的集成。
