Kinetic study of the hydrogenation of p-nitrophenol to p-aminophenol over micro-aggregates of nano-Ni2B catalyst particles

The present work concerns a thorough investigation of the performance of a nano-nickel boride catalyst for the direct hydrogenation of p-nitrophenol (PNP) to p-aminophenol (PAP) in a batch slurry reactor using ethanol as solvent. The effect of pH during the synthesis procedure on the properties of the assynthesized catalyst has been investigated using FTIR, XRD, ICP and FESEM analysis. The synthesized catalyst shows a better activity with respect to Raney nickel. The effect of catalyst preparatory method on its activity has been investigated. The effect of reaction temperature (40-80 degrees C). PNP initial concentration (0.07-0.28 g mL(-1)) and initial pressure (25-40 bar) on the reaction kinetics has been investigated. It has been shown that the kinetic behavior throughout the whole time domain could be reasonably predicted considering a single site mechanism with atomically adsorbed hydrogen and PNP adsorption as the controlling step. (C) 2011 Elsevier B.V. All rights reserved.