(513et) Continuous Synthesis of Pd-Carbon Catalysts Using a Spinning Disk Reactor: A Platform for Continuous Catalyst Production

Heterogeneous palladium (Pd)-carbon catalysts, as a commercial product, have proven to be effective for Suzuki cross-coupling reactions. The synthesis methods used in combination with specialty, batch synthesis methods enabled small Pd particles supported on graphene and result in turnover frequencies upwards of 100,000 h^-1. However, the inherent batch-to-batch variability in product properties, such as particle size distribution, associated with batch syntheses limited the expected physical property consistency for Pd supported catalysts. Continuous manufacturing technology could reduce catalyst variability during synthesis and enable larger scale operations producing materials of consistent quality. Continuous production of heterogeneous catalysts in the liquid-solid phase have been challenging due to processing limitations for controlling material properties. A spinning disk reactor (SDR) presents itself as a viable platform for continuous production of heterogeneous catalysts. The shear force and plug flow regime in thin films exhibited by the SDR resulted in rapid particle nucleation and growth of heterogeneous Pd-graphene catalysts with consistent product quality across batches. The synthesized samples were characterized by TEM and pulse chemisorption to determine the particle size distribution and quantify the catalytic active sites. Pd nanoparticles ranging from 2 to 50 nm were produced using the SDR and examined for catalytic activity in a Suzuki cross-coupling reaction.