In 2018, the EU's revised Renewable Energy Directive came into force, increasing renewable energy targets for all energy sectors while limiting the use of first‐generation biomass as feedstock. Fuel components like methanol, ethanol, propanols, and butanols represent promising candidates to enable the targets for transportation to be achieved because they can be used with existing infrastructure and can be further processed to give additives and substitutes. A wide variety of feedstocks and processes are available for this purpose. In this review, the thermocatalytic and biological synthesis routes for C1–C4 alcohol fuels are summarized to illustrate the many alternatives. They include biomass and waste gasification and carbon capture and utilization to obtain syngas for catalytic conversion, fermentation of sugars from lignocellulosic feedstock, and novel, less developed pathways like syngas fermentation, glycerol conversion, and biogas reforming. The current state of technology is presented by discussing the advantages and technical hurdles, and by introducing recent scaled‐up approaches. This demonstrates the need for further research and development. The assessment of techno‐economic analyses in the literature illustrates the dominant factors affecting production costs and reveals the broad range of feasibility of the various production routes. The review shows that the routes most similar to conventional, well‐established syntheses bear the highest potential to be implemented in the short and medium term. The availability of cheap and abundant feedstock also plays a crucial role. Methanol synthesis from biomass gasification and ethanol, and acetone‐butanol‐ethanol fermentation from lignocellulosic biomass, are therefore considered to be very promising. © 2020 The Authors. Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley & Sons Ltd.

中文翻译：

---

先进的可再生C1到C4醇作为生物燃料成分的生产路线–评论

2018年，欧盟修订的《可再生能源指令》生效，提高了所有能源行业的可再生能源目标，同时限制了使用第一代生物质作为原料。燃料成分（如甲醇，乙醇，丙醇和丁醇）是有希望的候选者，因为可以与现有基础设施一起使用，并且可以进一步加工以提供添加剂和替代物，因此有望实现运输目标。为此目的，可以使用多种原料和工艺。在这篇综述中，对C1-C4酒精燃料的热催化和生物合成路线进行了总结，以说明许多替代方案。其中包括生物质和废气气化以及碳的捕获和利用，以获取用于催化转化的合成气，木质纤维素原料中的糖的发酵，以及合成气发酵，甘油转化和沼气重整等较不发达的新途径。通过讨论优点和技术障碍，并介绍最新的扩展方法，介绍了当前的技术状态。这表明需要进一步的研究和开发。文献中对技术经济分析的评估说明了影响生产成本的主要因素，并揭示了各种生产路线的广泛可行性。审查表明，与常规的，完善的合成方法最相似的路线具有在短期和中期实施的最大潜力。廉价和丰富的原料的供应也起着至关重要的作用。因此，由生物质气化和乙醇合成甲醇，以及由木质纤维素生物质发酵丙酮-丁醇-乙醇被认为是非常有前途的。©2020作者。工业化学学会和John Wiley＆Sons Ltd.出版的生物燃料，生物产品和生物精炼。