Chair of Biochemical Engineering, School of Engineering and Design, Technical University of Munich, Boltzmannstr. 15, 85748 Garching, Germany.
Molecules. 2024 Jun 4;29(11):2661. doi: 10.3390/molecules29112661.
Electrocatalytic CO reduction to CO and formate can be coupled to gas fermentation with anaerobic microorganisms. In combination with a competing hydrogen evolution reaction in the cathode in aqueous medium, the in situ, electrocatalytic produced syngas components can be converted by an acetogenic bacterium, such as , into acetate, ethanol, and 2,3-butanediol. In order to study the simultaneous conversion of CO, CO, and formate together with H with , fed-batch processes were conducted with continuous gassing using a fully controlled stirred tank bioreactor. Formate was added continuously, and various initial CO partial pressures (pCO) were applied. utilized CO as the favored substrate for growth and product formation, but below a partial pressure of 30 mbar CO in the bioreactor, a simultaneous CO/H conversion was observed. Formate supplementation enabled 20-50% higher growth rates independent of the partial pressure of CO and improved the acetate and 2,3-butanediol production. Finally, the reaction conditions were identified, allowing the parallel CO, CO, formate, and H consumption with at a limiting CO partial pressure below 30 mbar, pH 5.5, n = 1200 min, and T = 32 °C. Thus, improved carbon and electron conversion is possible to establish efficient and sustainable processes with acetogenic bacteria, as shown in the example of
电催化 CO 还原为 CO 和甲酸盐可以与厌氧微生物的气体发酵相耦合。在水介质中阴极的竞争析氢反应的结合下，电催化原位产生的合成气成分可以被产乙酸菌，如 ，转化为乙酸盐、乙醇和 2,3-丁二醇。为了研究 与 CO、CO 和甲酸盐以及 H 的同时转化，采用完全控制搅拌槽生物反应器连续通气进行了分批进料实验。连续添加甲酸盐，并施加不同的初始 CO 分压（pCO）。 利用 CO 作为生长和产物形成的首选底物，但在生物反应器中 CO 分压低于 30 毫巴时，观察到同时 CO/H 转化。甲酸盐的补充使无论 CO 分压如何，生长速率提高了 20-50%，并提高了乙酸盐和 2,3-丁二醇的产量。最后，确定了反应条件，允许在限制 CO 分压低于 30 毫巴、pH 值为 5.5、n = 1200 min 和 T = 32°C 的条件下，用 进行 CO、CO、甲酸盐和 H 的平行消耗。因此，正如 的例子所示，通过产乙酸菌可以实现更好的碳和电子转化，从而建立高效和可持续的工艺。
