Continuously operating heterogeneous catalytic reactors are an important step towards more efficient and controllable processes compared to batch operation. Ideally, reactors should exhibit high permeability with the catalyst having a high surface area to volume ratio to minimize the required amount. An example of such catalyst morphology are nanoparticles with a plate-like morphology. In this work, the catalytic reactor was prepared by depositing plate-like silver nanoparticles on positively charged high internal phase emulsion monoliths by exploiting their negative zeta potential. The silver nanoplates had an edge length of 63 nm and a thickness of 13 nm with a sphericity factor of 0.548. The amount of deposited silver, determined from absorbance measurement and mass difference was 12.5 mg/ml and remained unaffected by the concentration of positively charged groups in the range between 69 and 110 mmol/l, demonstrating the robustness of the proposed approach. The permeability remained unchanged after silver deposition under flow due to the polymer microstructure. The reactor was found to be stable under various elution conditions, even after prolonged catalytic reduction of 4-nitrophenol. The specific catalytic activity of silver nanoplates was 428 min$^{−1}$ g$^{−1}$, which is an order of magnitude higher than that of silver nanoparticles with cuboctahedra shape and one of the highest reported. The proposed approach can be applied to various types of catalytic nanoparticles by exploiting a variety of possible interactions.