The conversion of CO2 into valuable chemicals by the use of renewable energy is an strategic goal for the sustainable development of the society in the near future. It will entail the reduction of greenhouse gas emissions, but also the generation of renewable compounds substituting fossil ones. CO2 generation from e.g. fermentation processes will offer excellent application opportunities for this concept, owing to their rather high carbon dioxide concentrations and their favorable chemical context (i.e. pure CO2 from alcoholic fermentations in bio-refineries, distilleries, etc.; biogas from anaerobic fermentation or landfills, containing 20-45 % CO2). However, a significant impact of the CO2-to-chemicals future processes will be achieved only if viable CO2 capture/purification technologies from the atmosphere or flue gases will be developed.
In that context, the CELBICON project aims at the development, from TRL3 to TRL5, of new CO2-to-chemicals technologies, conjugating at once small-scale for an effective decentralized market penetration, high efficiency/yield, low cost, robustness, moderate operating temperatures, low maintenance costs and high versatility to be adapted to the synthesis of a variety of chemical products.
The core goal of the Celbicon project is to ultimately produce high-value chemicals with a very low, or even negative, carbon footprint. This is done by capturing CO2 from the air and converting it to complex, valuable chemicals. The CO2 is converted by a sequence of electrochemical and biochemical steps. The energy required for the conversions can ultimately come from sustainable energy sources. More specifically, three reaction lines are performed (see Fig. 1). In the first reaction line (technological platform 1, TP1), after capturing CO2 from the air, it is electrochemically converted to high pressure syn-gas (CO and H2) and the oxidation of renewable chemical in a high value acid. Then, in technological platform 2 (TP2), the syn-gas is biochemically converted at elevated pressure to building blocks for bioplastics. In this biochemical conversion some CO2 is emitted again but it is recovered, together with excess captured CO2 from air, to be then converted in a second high-pressure bio-reactor to bio-methane. In the third reaction line (technological platform 3, TP3) demineralization of wastewater is done at the same time that air-captured CO2 is electrochemically converted to formate, which is subsequently biochemically converted to large valuable compounds, such as isoprenes.
