Fig. 2: Simplified process concept for the production of HyFiT fuels.

Process steps are depicted as boxes while arrows denote mass flows. The process concept combines at its core the FT synthesis and hydroformylation (light blue boxes). In the gas loop, tail gas is either purged (open loop) or treated (closed loop) to recycle unconverted carbon monoxide (CO; dashed arrows). Depending on the supply chain optimization, by-products, for example, aromatics and oxygenates, are either incinerated for heat recovery followed by optional CO₂ capture or flared. Note that we do not differentiate between the LT-FT and HT-FT syntheses for the sake of better readability. Detailed process flow charts of all involved process steps are in Supplementary Note 4.