Intrinsic Kinetics of Three-Phase Slurry Hydrogenation of o-Nitrocardanol to o-Aminocardanol over Raney Nickel Catalyst

The intrinsic kinetics of the hydrogenation of o -nitrocardanol (ONC) to o -aminocardanol (OAC) over Raney nickel (Ra/Ni) has been investigated with methanol as a reaction medium. The catalytic hydrogenation was carried out in an agitated three-phase slurry reactor, operating in the kinetically controlled regime. The operating conditions were varied with temperature in the range 60–90 °C, initial concentration of o -nitrocardanol in the range 5.73–14.3 mmol, hydrogen partial pressures in the range 8–20 bar, and catalyst loading in the range 0.25–0.75 g dm –3 . Catalyst reusability was also examined. The reaction was found to follow first-order kinetics with respect to both hydrogen and o -nitrocardanol. The Langmuir–Hinshelwood–Hougen–Watson (LHHW) approach was used to investigate the possible mechanistic path of the reaction. It was found that the reaction proceeds through dual site molecular adsorption of reactant species with the surface reaction being the rate-controlling step. Also, the various thermodynamic properties associated with various rate constants were estimated.