Harnessing the potential of fusel oil to produce high-purity renewable hydrogen via intensified steam reforming over Ni-Ce/CaO-based bifunctional materials

Fusel oil (FO), a residual by-product of bioethanol production, is an abundant yet underutilized resource rich in multi‑carbon alcohols. To valorize this overlooked industrial waste into valuable products, this research investigates the sorption-enhanced steam reforming of FO (SE-FOSR) as a novel, eco-friendly intensified process for renewable high-purity hydrogen production. SE-FOSR combines catalytic steam reforming with in-situ CO 2 capture over Ni-Ce/UGSO-CaO hybrid materials (either as bifunctional materials (BFMs) or as a mechanical mixture of catalyst and sorbent), shifting the water-gas shift (WGS) equilibrium and enhancing H 2 production. BFMs, integrating catalytic and sorbent functions in single particles, outperformed mechanical mixtures with up to 50% higher H 2 yield and 42% greater FO conversion. Compared to the Ce-free BFM, the Ce-promoted BFM (Ni-Ce/(UGSO-CaO)) achieved higher H 2 hydrogen purity (97 vs 96%), H 2 yield (58.9 vs 56.9%), and FO conversion (56.3 vs 51.3%), with minimal co-production of methane, CO, and liquid by-products (more than 50% reduction), as well as enhanced stability under cyclic SE-FOSR experiments. Comprehensive characterization revealed that i ) the incorporation of UGSO, a non-valorized metallurgical residue, promoted strong metal-sorbent interactions, and ii ) well-dispersed Ni/Ce particles within the CaO matrix improved sintering resistance during cyclic operation. Ce promotion enhanced WGS activity via its reversible Ce 4+ /Ce 3+ redox cycle, facilitating oxygen vacancy formation and H 2 O activation, while also limiting Ni sintering and coke deposition, thus stabilizing performance. This work offers a novel route for FO valorization and provides valuable insights for designing advanced BFMs to intensify alcohol steam reforming processes. • Low-value fusel oil (FO) valorized as promising novel source of renewable hydrogen • FO converted into highly pure H 2 by innovative intensified steam reforming process • Ni/Ce/CaO-based hybrid materials achieved successful process intensification • Performance boosted by synergy in bifunctional materials over physical mixtures • Ceria promotion was to key to improve WGS activity, limit sintering and coking