Oxidative decarboxylation of fatty acids represents a promising hydrogen-free route for hydrocarbon production, yet catalytic systems operating under moderate aerobic conditions with kinetic and mechanistic validation remain limited. In this study, a biomimetic Mn–Cu catalytic system was evaluated for the oxidative decarboxylation of lauric acid at 110–150 °C under continuous air flow. Reaction performance was assessed through CO₂ evolution as a kinetically relevant indicator of carboxyl-group cleavage, enabling real-time evaluation of decarboxylation activity. The Mn–Cu system exhibited substantially higher catalytic activity than the corresponding monometallic Mn- and Cu-based systems, indicating cooperative interactions between the two metal components. Kinetic analysis showed that the reaction proceeded under an oxygen-coupled regime without an observable induction period. The initial CO₂ formation rate under air reached 0.1863 mmol min⁻¹, approximately 9.3 times higher than that under N₂, confirming the essential role of oxygen in sustaining catalytic turnover. Radical trapping experiments using butylated hydroxytoluene (BHT) resulted in concentration-dependent inhibition of CO₂ formation, reaching up to 73.3%, supporting the involvement of radical species in the decarboxylation pathway. GC–MS analysis confirmed hydrocarbon formation, with C11 compounds as the dominant fraction, consistent with lauric acid decarboxylation. A plausible Mn–Cu-assisted oxygen-coupled pathway is proposed, in which Cu contributes to oxygen activation while Mn facilitates carboxylate oxidation through electron-transfer processes. However, specific Cu–oxygen species, Mn oxidation states, and radical intermediates were not directly identified. Overall, these findings provide coherent kinetic and mechanistic evidence for Mn–Cu-assisted oxidative decarboxylation under moderate aerobic conditions. Copyright © 2027 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).