Enhanced biodiesel synthesis from sunflower oil in an integrated plasma‐jet and bubble reactor

Abstract Biodiesel is a renewable alternative to fossil fuels, and sunflower oil is a promising feedstock because of its favorable fatty‐acid composition. This study developed and optimized an integrated atmospheric plasma jet‐bubble reactor for the transesterification of refined sunflower oil. The configuration combines plasma exposure at the liquid surface with gas‐induced mixing from the bottom of the reactor while mechanical stirring is maintained. A four‐factor Box–Behnken design was used to evaluate temperature, methanol‐to‐oil molar ratio, KOH concentration, and residence time. The model predicted optimum conditions of 42.51°C, a methanol‐to‐oil molar ratio of 5.79:1, 0.97 wt% KOH, and a residence time of 29.92 min, corresponding to a predicted FAME content of 95.89%. A confirmation experiment yielded 94.36% FAME. These findings demonstrate the potential of the integrated plasma jet–bubble reactor as a process‐intensification strategy for achieving high FAME content within a relatively short residence time. Further investigation of energy consumption, fuel properties, and plasma‐assisted reaction mechanisms is required to establish its broader practical and sustainability benefits.