Polyvinylpyrrolidone-stabilized Pt colloidal catalysts in chloronitrobenzene hydrogenation and modification with rare earth ions

Abstract

Polyvinylpyrrolidone (PVP)-stabilized Pt colloidal catalysts with hydrazine hydrate as a reductant were prepared in an H 2 PtCl 6 water solution/PVP/nbutanol microemulsion system. With m-chloronitrobenzene (m-CNB) selective hydrogenation as a probe, we studied how the microemulsion composition as well as the reduction conditions would affect the hydrogenation performance of PVP-Pt. The effects of rare earth ions on the modification of PVP-Pt were further studied. The as-prepared PVP-Pt improved the m-CNB hydrogenation activity and significantly enhanced the reactive selectivity compared with the ethanol reflux method. The addition of a small amount of Pr 3? -modified PVP-Pt/Pr (Pt:Pr molar ratio of 1:0.14) further improved the activity of the catalyst.