Preparation of nano-dispersed palladium particles on alumina support is described here using reverse microemulsion (water-in-oil) method. This synthesis protocol leads to a narrow Pd particle size distribution with particles of average size, which were significantly smaller compared to those prepared by classical impregnation method. It is shown that the particle size could be effectively controlled both by the microemulsion chemical composition such as concentration of PdCl2 and the water/surfactant molar ratio and by the catalyst reduction process. Under the optimal reaction conditions, a Pd/Al2O3 catalyst with a homogeneous distribution of Pd particles of average size ~2.2 nm was obtained.
Part of the book: Noble and Precious Metals