Interface-active amphiphilic janus microreactors as stabilizers of pickering emulsions for green biodiesel production

The production of biodiesel from renewable feedstocks through energy-efficient processes remains a pressing challenge. Pickering emulsions, stabilized by solid particles, have emerged as a promising approach to enhance biodiesel production. This study presents the synthesis of dumbbell-shaped Janus polymer nanoparticles (DS-JPNs) functionalized with organic amine bases, which serves as Pickering interfacial catalysts (PICs) for transesterification reaction. The anisotropic morphology and amphiphilic nature of DS-JPNs promote stable adsorption at the soybean oil-methanol interface, leading to reduced interfacial tension, smaller droplet formation, and the generation of thermodynamically stable emulsions. This microreactor system prominently enhances the interfacial area and mass transfer efficiency, thereby accelerating the transesterification efficiency. Consequently, the DS-JPN-TMA catalyst achieved a biodiesel yield of 85.4 % under static conditions, a 2.6-fold increase compared to the spherical PS-TMA counterpart (34.2 %). Among the examined Janus organic base catalysts, DS-JPN-TBD demonstrated the highest catalytic performance (TOF 12.51 h −1 ), attaining a biodiesel yield of 96.7 %, attributable to the strong basicity of its bicyclic guanidine moieties. Furthermore, DS-JPN-TBD retained 94.2 % of its catalytic activity after five reaction cycles, evidencing excellent reusability and durability. This study underscores DS-JPN-TBD as an innovative, energy-efficient, and sustainable solution for biodiesel production and proposes a scalable strategy for green energy applications.