生物−电催化转化二氧化碳的高值化利用研究进展

Research progress on value-added utilization of carbon dioxide through bio-electro-catalysis

中国是世界上最大的二氧化碳(CO_(2))排放国和煤炭消费国,且以煤为主的能源结构短期内难以改变。在“碳达峰”和“碳中和”背景下,将CO_(2)捕集、存储或将其利用转化为高价值燃料和化学品,可减少对化石燃料依赖并同时降低CO_(2)排放,为燃煤电厂和能源化工的绿色转型提供关键技术支撑。电催化和微生物转化是利用CO_(2)生成可再生燃料及化学品的重要途径。电催化还原CO_(2)反应速率快,但产物种类多限于C_(1)和C_(2)的产物。微生物固定CO_(2)产物选择性高、多碳产物种类多,但电子传递和能量供给水平低导致反应周期长。将电催化还原CO_(2)和微生物转化耦合,可充分发挥两者的优势,有望实现高效制备高价值的多碳产物。分别介绍了单一技术路线下电催化还原和微生物固定CO_(2)的反应原理和典型产物,讨论了催化剂和反应器类型对电催化还原CO_(2)的影响,总结了微生物固定CO_(2)的微生物种类和生物代谢路径;综述了原位耦合和异位耦合2种电催化−微生物转化技术的耦合方式,概括了其系统构成、工作原理、电极材料及高值产物类型等。最后,对比了不同耦合方式的技术成熟度,并从电催化还原CO_(2)催化剂和反应器的开发和设计、高效工程菌种的构建、耦合体系的设计与集成和推动研究开发与产业联动4个方向进行展望。

China is the world’s largest CO_(2)emitter and coal consumer,and its coal dominated energy structure is difficult to be changed in the short term.In the context of carbon peaking and carbon neutrality,the capture and storage or conversion of carbon dioxide into renewable fuels and chemicals can reduce dependence on fossil fuels and at the same time reduce CO_(2)emissions,providing key technical support for the green transition of coal-fired power plants and energy chemicals.Electrocatalysis and microbial conversion are important ways to produce renewable fuels and chemicals from carbon dioxide.The reaction rate of electrocatalytic reduction of CO_(2)is high,but the products are mostly limited to C_(1) and C_(2) products.Microbial CO_(2)fixation has the advantages of high selectivity and variety of products.However,the low electron transfer and energy supply lead to a long reaction period in the microbial CO_(2)fixation.Integration of electrocatalysis and microbial conversion can play their advantages to efficiently produce the value-added multi-carbon products.In this paper,firstly,the reaction principles,typical products of electrocatalysis and microbial CO_(2)fixation under a single technical route were introduced respectively.The catalyst and reactor of electrocatalytic CO_(2)reduction were discussed,and the microbial species and biological metabolic pathways of microbial fixation of CO_(2)were summarized.Secondly,two methods of the integration of electrocatalysis and microbial conversion was reviewed,and the system structure,working principle,elec-trode materials and value-added products were analyzed.Finally,the technology readiness level of different coupling methods was compared,and the future prospects were highlighted from four aspects:the catalysts for electrocatalytic CO_(2)reduction,the engineered microbial strains,the design and integration of coupling systems and the linkage between aca-demic research and industry.