Biofilm‐Based Continuous Succinic Acid Production From Complex Feedstocks With In Situ Recovery

Succinic acid (SA) is an important C4 platform chemical for renewable polymers and value‐added products, but bio‐based production is still limited by costly substrates, cell washout, inhibitor stress, inefficient carbon dioxide transfer, and demanding downstream recovery. This review examines biofilm‐based continuous fermentation as an integrated process‐intensification route for SA biomanufacturing. Biofilm and immobilized‐cell reactors are discussed as high‐cell‐density systems that retain biomass, stabilize metabolism, and support complex feedstocks such as lignocellulosic hydrolysates, food‐processing residues, and crude glycerol. Advances in feedstock pretreatment, inhibitor mitigation, carbon dioxide utilization, bicarbonate delivery, and in situ product removal are evaluated for continuous operation. Strain engineering for biofilm formation, inhibitor tolerance, metabolic robustness, and microbial consortia is also considered. The review highlights that coupling feedstock conditioning, biofilm fermentation, product recovery, and microbial engineering is essential for carbon‐efficient and circular SA biorefineries.