This PhD project within ECOMO research project focuses on exploring fermentation of CO to acetic acid by axenic acetogenic cultures and highly specialized mixed microbial consortia in a novel reactor type.
With a growing global population and increasing consumption of fossil fuels, there is an urgent need to develop technologies that can produce commodity chemicals from renewable resources. Gasification of biomass, along with the subsequent biological conversion of the generated syngas (mainly a mixture of CO, CO2, and H2), gains growing interest. The technology developed for syngas bioconversion can also be effectively applied to the treatment and valorization of CO-containing waste gases from different industries.
The fermentation of CO is carried out by acetogenic bacteria, producing mainly acetic acid and ethanol via the Wood-Ljungdahl pathway. Complete conversion of CO though requires additional electron sources. In the frame of the PhD project, we will investigate supplementation of either hydrogen or electricity in a novel reactor type as potential electron donors. In-line acetic acid extraction by an electrolytic cell will support optimization of the product titer for efficient, highly specific CO conversion to acetic acid as well as optimal titer for the subsequent step, i.e., acetic acid conversion to diamine monomers by our partners in the Horizon EIC project ECOMO.
The objectives of the PhD project are:
- Enriching and characterizing highly specialized mixed microbial consortia that are CO-tolerant, highly specific towards acetic acid production, and electroactive.
- Examining carbon and electron flows to final products under different operational conditions.
- Developing and operating a novel reactor – benchmarking its efficiency against the efficiency of conventional reactor types.
- Integrating the gas fermentation with in-situ acids removal by an electro-membrane cell.