The intrinsic kinetics of the hydrogenation reaction of 1,5-cyclooctadiene (COD) to cyclooctene (COE) and of COE to cyclooctane (COA) was investigated in a wide range of reaction conditions: 40-70 degrees C, 0.2-1 MPa hydrogen pressure, and an initial COD concentration of 0.41-0.82 mol/L with a fine powder (100 mu m grain size) of a Pd/alpha-Al2O3 catalyst in a slurry reactor. Reaction rates were found to depend on COD, COE, and hydrogen concentrations according to a Langmuir-Hinshelwood-type rate law. Rate constants and activation energies were determined by fitting the kinetic model to experimental data. Activation energies of 74 kJ/mol for the reaction of COD to COE and of 98 kJ/mol for the reaction of COE to COA were determined.