Catalysis with soluble hybrids of highly branched macromolecules with palladium nanoparticles in a continuously operated membrane reactor

The continuous recovery and recycling of sol. metal nanoparticles by means of ultrafiltration is described, employing hybrids of palladium nanoparticles with highly branched amphiphilic polyglycerol as a catalyst for cyclohexene hydrogenation as a model reaction. In a continuously operated membrane reactor a productivity of 29000 TO over 30 exchanged reactor vols. was obsd. for nanoparticles of 2.2 nm size, with a max. rate of 1200 TO h-1. Catalysis by sol. metal complexes can be excluded. After 30 h of operation, some decrease in activity is obsd. which is due to deposition of palladium on the ultrafiltration membrane, however this material does not contribute to catalytic activity