合成气生物发酵法制乙醇的研究进展

采用合成气生物发酵法制乙醇具有反应条件温和、产物选择性高、原料来源广泛、低碳可持续发展等优势，是一种具有前景的可再生能源新型生产工艺。文章综述了合成气发酵法制乙醇的微生物种类及对应的适宜操作条件，分析了合成气发酵法制乙醇的Wood-Ljungdahl代谢途径；总结了合成气的广泛来源；分析讨论了过程工艺参数如合成气组成及压力、pH、温度、培养基组分、气液传质对合成气发酵的影响；指出合成气发酵法制乙醇面临的底物传质性能差、乙醇收率低等关键问题，比较了典型反应器在传质方面的差异，归纳了传质强化方法；总结了合成气发酵法制乙醇的工业化进展， 并提出了未来的发展方向。

Review of ethanol production via biological syngas fermentation

Syngas bio-fermentation to produce ethanol has the advantages of mild reaction conditions, high product selectivity, wide source of raw materials, and low-carbon sustainable development. It is a promising new production process for renewable energy. The species of microorganisms and corresponding suitable operating conditions for ethanol production via syngas fermentation are reviewed. The Wood-Ljungdahl pathway of syngas fermentation is analyzed and the extensive sources of syngas are summarized. The effects of the process parameters, such as the composition of syngas, pressure, pH, temperature, medium component and gas-liquid mass transfer on syngas fermentation, are analyzed and discussed. The key problems of poor mass transfer performance of gas substrate and low ethanol yield in the syngas fermentation process are pointed out. The different mass transfer performance of typical bioreactors is compared, and the approaches to enhancing mass transfer are reviewed. Finally, the industrialization progress of ethanol production by syngas fermentation is reviewed, and the future development direction is proposed.