Palladium Nanoparticles Inset into the Carbon Sphere with Robust Acid Resistance for Selective Hydrogenation of Chloronitrobenzene

Abstract

Most of the catalytic hydrogenation reactions take place under high temperature, high pressure, and high corrosion, which poses a challenge to the activity and stability of hydrogenation catalysts. Herein, an acid resistant and strawberry-like metal–carbon sphere (M/SCS) as a robust hydrogenation catalyst was synthesized by a one-step method. Self-assembled metal nanoparticles gather and are embedded on the surface of the carbon sphere prepared by the carbonization of phenolic resin. By means of the surrounding carbon layer, the acid resistant capability is orders of magnitude intensified compared to traditional commercial catalysts. Over 91.5% and 100% metals of Pd/SCS7 and Pt/SCS7 remain as the catalyst in hydrochloric acid (36–38 wt %), while less than 44.6% and 37.5% metals remain of commercial Pd/AC and Pt/AC. In addition, the sizes are controlled in the range of 11 to 18 nm for metal particles and 400 to 1600 nm for carbon spheres by adjusting the conditions of phenolic aldehyde condensation. N atoms anchored on the carbon spheres with high dispersion can improve electron density on metal particles. M/SCS exhibits both excellent stability and high catalytic performance in the hydrogenation reactions.