In the first period of the project, we have developed a new type of alkaline water electrolyzer, powered fully by integrated photovoltaic (PV) modules into a single unit. Research and developments are being conducted on novel efficient electrocatalysts for the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER), but also show high durability for water splitting under intermittent conditions. These are key challenges in the scientific community and REFINE is contributing with not only high performing catalysts, but also catalysts made of sustainable materials and processes. Materials selection and unit modelling are central aspects that guide the catalyst developments so that we optimize performance and sustainability. In parallel, bioengineered bacterial cultures are developed for the selective synthesis of isobutanol directly from the H2 and O2 produced by the electrolysis unit and the industrial CO2 emissions. It is important to notice that these are autotrophic conditions (presence of only CO2 and H2) and we have already seen bacterial growth comparable to heterotrophic conditions (sugars as carbon source instead of just CO2). Another key aspect in our bioengineering processes is the adaptation of the bacteria that survive under high amounts of isobutanol, which is otherwise toxic above certain levels. This has been achieved by high-end strain and DNA manipulations with targeted biological pathways.
In the next phase we will combine the two processes into one, effectively providing a true and robust system of artificial photosynthesis, transforming CO2 and H2 to isobutanol of high selectivity and purity.
