M. Sc. Arno Windisch

Homogeneous transition metal catalysts offer several advantages over their heterogeneous counterparts, including high activity and selectivity, even under relatively mild operating conditions. Despite these strengths, most industrial processes rely on heterogeneous catalysis due to the simpler and more cost-effective separation of products from the catalyst. A notable example is the hydrogenation of aldehydes, which is typically catalyzed heterogeneously, even though the aldehydes themselves are often produced through homogeneous catalysis.

Integrating these two reaction steps into a single tandem catalytic process presents a sustainable and efficient route to alcohol production using a single catalyst. However, a significant challenge lies in the fact that the two steps require distinct reaction conditions to proceed efficiently. Capillary flow reactors provide a practical solution for implementing these varying conditions. For instance, in the reductive hydroformylation process, the carbon monoxide necessary for hydroformylation inhibits the subsequent hydrogenation step.

By employing modular setups with intermediate CO removal, the tandem reaction was successfully implemented, though further optimization is still needed. Moreover, this concept has the potential to be extended to other sequential reactions, paving the way for more efficient catalytic processes in the future.