Experimental and theoretical studies on the partial hydrogenation of vegetable oil in a monolithic stirrer reactor are reported. A complete mathematical model of the reactor was developed, including hydrogenation and isomerization kinetics, catalyst deactivation, external gas-liquid and liquid-solid as well as internal mass transfer. The experimental studies were carried out in a Pd/Al2O3/Al monolithic stirrer reactor, at a wide range of temperatures (353-373 K), pressures (414-552 kPa), and catalyst loadings (0.00084-0.00527 kg(Pd,exp) m(-3)). Based on this model, simulated data can be used to evaluate the catalyst (Pd/Al2O3/Al) and the hydrogenation process in consecutive catalytic tests under different operating conditions. (c) 2014 American Institute of Chemical Engineers AIChE J, 60: 3524-3533, 2014