Platinum nanoparticles encapsulated in HZSM-5 crystals as an efficient catalyst for green production of p-aminophenol

An intimately bifunctional catalyst composed of Pt nanoparticles encapsulated in crystals of HZSM-5 zeolite has been studied for one-pot hydrogenation of nitrobenzene (NB) to p-aminophenol (PAP) without the use of inorganic acid. The cooperation between the Pt-encapsulated nanoparticles and surrounding acid sites of HZSM-5 endowed the catalyst excellent performance, high selectivity and good recyclability, for the environmentally benign production of PAP. Interesting and importantly, the cooperation effect between metallic Pt sites and acid sites intimately surrounded affected the PAP selectivity and those acid sites that a little longer apart from the platinum particles were basically invalid.