The kinetics of oligomerization of isobutene was studied on a NiSO4/gamma-alumina catalyst in a stirred batch autoclave at temperatures of 50-90 degrees C and a pressure of 2170 kPa with different concentrations of isobutene. Experimental results revealed that the catalyst has high dimer selectivity and did not show any significant deactivation during the reaction. A generalized kinetic model based on a Langmuir-Hinshelwood (LH)-type reaction sequence was developed. The intraparticle diffusion effects inside the catalyst particle were correlated to the reaction rates and mass-transfer rate between the catalyst particle and liquid phase. The developed intrinsic kinetic model with estimated model parameters was found to describe the experimental data accurately. The magnitude of the activation energies was found to be in the range of 13-27 kJ mol(-1), which suggests that the oligomerization reaction proceeds via surface rearrangement, as considered in the present LH-type kinetic model.