Bio-electrified hydrocarbons from cascading conversion of biowaste

Advanced biofuels in the form of liquid hydrocarbons offer a pathway to decarbonize long-distance heavy transport. Integrating biological acidification with electrocatalytic Kolbe-type decarboxylation provides a promising route for selectively producing linear hydrocarbons from biowaste. However, such cascading systems face challenges including suboptimal carbon utilization, limited product selectivity, and energy-intensive separations. This paper explores microbial chain elongation for generating medium-chain carboxylic acids (MCCAs) from biowaste, alongside CO₂ reduction to supply biocompatible electron donors and improve carbon efficiency. Particular attention is placed on waveform-controlled electrosynthesis, which enables selective upgrading of MCCAs into alkanes and alkenes under mild conditions. Framed within a circular bioeconomy, key mechanistic, engineering, and techno-economic gaps are identified to advance bio-electrified hydrocarbons as competitive drop-in fuels.