Sustainable biodiesel production from wild oak (Quercus brantii Lindl) oil as a novel and potential feedstock via highly efficient Co@CuO nanocatalyst: RSM optimization and CI engine assessment

The nanostructured Co@CuO heterogeneous catalyst was synthesized through the sol-gel route for biodiesel generation from Quercus brantii Lindl oil (QBLO) as a novel feedstock. The surface features of Co@CuO nanocatalysts were scrutinized using several approaches including XRD, FTIR, Raman, TGA, EDX/mapping, FESEM, TEM, and BET. The characterization outcomes illustrated that the Co element was successfully incorporated into the CuO structure. The response surface methodology (RSM) and central composite design (CCD) were utilized to optimize transesterification variables. The highest biodiesel yield using prepared Co@CuO nanoparticle was obtained at 95.75% under optimum situations; methanol to QBLO ratio 10.08:1 mol/mol, reaction temperature: 59.73 °C, and nanocatalyst dosage: 2.88 wt%. The reusability appraisal displayed that the Co@CuO heterogeneous nanocatalyst can be exceptionally reused for 7 rounds (yield of 84.32%). Kinetic and thermodynamic analysis revealed that the transesterification reaction is first-order and endothermic. Moreover, the activation energy for biodiesel synthesis utilizing Co@CuO nanocatalyst was attained at 42.06 kJ mol−1. The compression ignition (CI) engine examination outcomes reveal that the rich oxygen quantity of biodiesel causes substantial improvements in performance and emission, mainly in the B20 blend (20% biodiesel+ 80% diesel). This research presents QBLO and Co@CuO nanocatalyst as a novel and potential incorporation for biodiesel production.