we need new, scalable feedstock streams. Waste carbon offers a way to unlock that scale. By combining captured carbon dioxide (CO₂) from industrial facilities with renewable hydrogen, or fermenting waste carbon monoxide (CO) gases into ethanol, producers can create a low-carbon liquid intermediate untethered from food crops or virgin land. That ethanol can then be upgraded via the AtJ process into a drop-in SAF with similar performance to HEFA, but with a much lower indirect land-use risk. In the case of marine fuel, it could be used to complement methanol use in ships. Because ethanol is already a globally traded commodity with existing storage and transport infrastructure, logistics are simpler compared to some emerging bio-feedstocks
ArcelorMittal’s chemical production facility using LanzaTech’s technology in Ghent, Belgium
Converting industrial carbon into ethanol LanzaTech’s gas fermentation technology uses microorganisms that can metabolise carbon- rich gases from industrial emissions. This gas may include CO, CO₂, and hydrogen, which are converted into ethanol in an energy-efficient manner. When adding more hydrogen to the gas, more carbon can be captured. These gases, typically considered waste or by-products of industrial processes, are thus ‘recycled’ into valuable ethanol. Ethanol’s flexibility as an intermediate Ethanol proves to be an extraordinarily flexible intermediate for various fuel applications. Its chemical properties allow it to be transformed into higher energy density fuels such as those required in aviation. The AtJ synthesis pathway is one such transformation, where ethanol undergoes dehydration to form ethylene, which
capacity around ethanol from waste carbon today position themselves for large-scale, policy-favoured SAF production tomorrow, while those locked into finite feedstocks risk hitting a ceiling. As policy criteria tighten, the market will increasingly reward feedstocks that can prove real, additional greenhouse-gas reductions at scale – exactly where waste- carbon routes shine. Emerging role of waste-based ethanol Most current SAF volumes come from hydroprocessed esters and fatty acids (HEFA), essentially upgraded waste oils and animal fats. These pathways have proven technology and certification routes, but they are constrained by limited feedstock supply and rising competition from the road transport and chemical sectors. If aviation (and marine) are to meet their ambitious net-zero goals,
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