High-throughput screening of supported catalysts in massively parallel single-bead microreactors: Workflow aspects related to reactor bonding and catalyst preparation

We demonstrate the possibility to anodically bond a 625-parallel single-bead microreactor filled with supported catalysts resulting in a hermetically closed reactor assembly. The bonding process enables excellent microfluidic properties by eliminating fluidic cross-talk between adjacent microreaction chambers. The bonding significantly facilitates handling of the reactor assembly, including mounting, dismounting, archiving, regeneration and re-use of the reactor, and protection of the catalytic materials. Regarding the comparison of a single-bead, non-contact incipient wetness preparation method with the corresponding conventional laboratory scale catalyst synthesis procedures, we show that the miniaturized single-bead synthesis is almost as accurate and reproducible as the conventional approach. The standard deviation of the observed conversion degree of the individually prepared single-bead catalysts in CO oxidation as model reaction is quantified to be in the range of 5-7%, while it is in the range of 3-6% for conventionally prepared catalysts. Both bonding and single-bead catalyst preparation enable a complete massively parallel single-bead workflow that may be a very accurate, elegant and last but not least highly competitive approach for high-throughput catalyst screening programs.