基于微生物电合成原理的二氧化碳回收和转化机理研究

开发新型的生物技术进行CO2的回收和资源化利用，对减少温室气体排放和实现污水生物处理无害化具有重要意义。微生物电合成系统（Microbial electrosynthesis system, MES）可利用微生物以废水作为产电基质,并将产生的CO2电还原合成有机酸或甲烷，有望实现废水的无害化和资源化。然而，MES的关键作用机理目前尚不清楚。本研究拟通过电化学条件控制、液相和气相成分实时分析、分子生物学测定的方法，对MES中阴极材料与电合成产物的关系、阴极控制电势对生物阴极的影响机制、产乙酸菌和产甲烷菌之间的协同或竞争机制进行深入探讨，以期探明电合成活性微生物与阴极之间的电子传递机理，实现污水处理过程有机物高效降解及CO2有效回收的目标。研究结果对实现废水的高效处理和CO2的资源化回收具有重要的科学指导意义。

To reduce emissions of greenhouse gas and realize the harmless of wastewater treatment,it is significant to develop novel biotechnology for the recovery and utilization of CO2. Microbial electrosynthesis system (MES)is a recently conceived bioenergy strategy in which acetogenic bacteria could accept electrons from negatively charged graphite electrodes as the electron donor for the reduction of CO2 to acetate that was released extracellularly. MES offer an opportunity to realize resource and harmless of wastewater treatment, as it can capture electrons from wastewater and further use them to produce useful organic chemicals by in-situ CO2 reduction. However, mechanisms for electron transfer from electrodes to microbes are still poorly understood. In this project, chemical, electrochemical and molecular biology methods will be adopted to investigate the effect of cathode set potential on the formation of microbial communities and product composition, the performance of diversity of cathode materials for microbial electrosynthesis, and the competition of electrons among diversity of species in a co-culture MES system. The object of this project is to provide clear informantion about mechanism of electron transfer between bacteria and solid electrode,and realize the integrated utilization of CO2 and maximization of organic removal rate from wastewater with optimization design of the MES. The study will provide an alternative for the CO2 capture from the environment, which will highlight an important scientific meaning for the resource and utilization of wastewater in the future.