The liquid-phase deoxygenation reaction of unsaturated renewables has been investigated in a semi-batch reactor. The reactants examined were the monounsaturated fatty acid, oleic acid, the diunsaturated fatty acid, linoleic acid and the monounsaturated fatty acid ester, methyl oleate. The reactions were carried out over a Pd/C catalyst under constant pressure and temperature in the following domain, 15-27 bar and 300-360 degrees C, respectively. The influence of carrier gas was additionally investigated. The impact as solvent (mesitylene) was studied as well and reaction pathways were proposed. Furthermore, continuous deoxygenation experiments were conducted, facilitating understanding of the catalyst stability and catalyst deactivation. The deoxygenation catalyst was characterized by physisorption, temperature programmed desorption (TPD), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). (C) 2007 Elsevier Ltd. All rights reserved.