Department of Molecular Biosciences and Bioengineering, University of Hawai'i at Mānoa, Agricultural Science Building 218, 1955 East-West Road, Honolulu, Hawaii 96822, USA.
Bioresour Technol. 2010 Jul;101(13):5013-22. doi: 10.1016/j.biortech.2009.12.098. Epub 2010 Jan 21.
The conversion of biomass-derived synthesis gas (or syngas in brief) into biofuels by microbial catalysts (such as Clostridium ljungdahlii, Clostridium autoethanogenum, Acetobacterium woodii, Clostridium carboxidivorans and Peptostreptococcus productus) has gained considerable attention as a promising alternative for biofuel production in the recent past. The utilization of the whole biomass, including lignin, irrespective of biomass quality, the elimination of complex pre-treatment steps and costly enzymes, a higher specificity of biocatalysts, an independence of the H(2):CO ratio for bioconversion, bioreactor operation at ambient conditions, and no issue of noble metal poisoning are among the major advantages of this process. Poor mass transfer properties of the gaseous substrates (mainly CO and H(2)) and low ethanol yield of biocatalysts are the biggest challenges preventing the commercialization of syngas fermentation technology. This paper critically reviews the existing literature in biomass-derived syngas fermentation into biofuels, specifically, different biocatalysts, factors affecting syngas fermentation, and mass transfer. The paper also outlines the major challenges of syngas fermentation, key performance index and technology road map, and discusses the further research needs.
在过去的一段时间里，利用微生物催化剂（如 Clostridium ljungdahlii、Clostridium autoethanogenum、Acetobacterium woodii、Clostridium carboxidivorans 和 Peptostreptococcus productus）将生物质衍生的合成气（简称 syngas）转化为生物燃料，已引起人们的极大关注，这是生物燃料生产的一种很有前途的替代方法。该过程的主要优点包括：利用包括木质素在内的整个生物质，不考虑生物质质量；消除复杂的预处理步骤和昂贵的酶；生物催化剂具有更高的特异性；生物转化对 H(2)：CO 比不依赖；在环境条件下操作生物反应器；不存在贵金属中毒问题。气体底物（主要是 CO 和 H(2)）的传质性能差和生物催化剂的乙醇产率低是阻止合成气发酵技术商业化的最大挑战。本文批判性地回顾了生物质衍生的 syngas 发酵生产生物燃料的现有文献，特别是不同的生物催化剂、影响 syngas 发酵的因素和传质。本文还概述了 syngas 发酵的主要挑战、关键性能指标和技术路线图，并讨论了进一步的研究需求。
