Waste-Based Volatile Fatty Acids for Fuel and Chemical Production

Volatile fatty acids (VFAs) are versatile intermediates for circular chemical and fuel manufacturing. Current VFA production relies heavily on fossil feedstocks and serves a narrow set of commodity markets. Here, we project VFA demand through 2050 and evaluate the potential to recover VFAs from abundant, widely available waste streams, exploring how waste-derived VFAs can support a broader circular carbon economy by midcentury. We project that the global VFA recovery potential from waste could reach ∼581 Mt yr^-1 by 2050, roughly 10 times higher than projected demand in existing markets. Integrating waste-carbon streams with anaerobic digestion infrastructure and emerging VFA production and separation technologies provides a feasible route for large-scale waste-to-VFA conversion. We project that in a 2050 circular scenario, ∼581 Mt yr^-1 of waste-derived VFAs can be flexibly distributed across various chemicals and energy sectors, supplying a significant portion of anticipated demand and establishing VFAs as a scalable, multifunctional platform molecule for a circular carbon economy.