Preparing Hydroxylamine Sulfate via the Hydrogenation of NO on Pt/Graphite Catalysts III: Functionalizing the Surfaces of Supports and the Formation of the Active Component when Synthesizing the Catalyst

The authors reveal aspects of the formation of platinum nanoparticles and chemical coating of carbon support surfaces when preparing model (0.5%Pt/Sibunite) and industrial (0.5%Pt/Graphite) catalysts for synthesizing hydroxylamine sulfate via the hydrogenation of NO in a solution of H2SO4. It is shown that functionalizing the surfaces of supports with nitrogen-containing groups while depositing platinum ensures not only the dispersion of metal but a strong increase in its selectivity toward hydroxylamine sulfate. It is assumed that maximum selectivity is characteristic of active sites being single atoms or small platinum clusters bound to the nitrogen-containing ligands of a carbon surface.