A correlation between the volumetric hydrogen mass transfer coefficient (KLa) in SRC-II process slurry and specific power consumption in mixing (E/VR) is developed. This correlation is independent of reactor configuration and it is also in very good agreement with the literature correlations forKLa. It is unified with an intrinsic hydrogen reaction rate expression to simulate the rate of hydrogen consumption in the SRC-II process. The simulation is validated by experimental data from an SRC-II continuous stirred tank reactor (CSTR). The mass transfer effects are interpreted and related to changes in product quality and a reduction in hydrogen reaction rate. Critical mixing power, required to maintain kinetically controlled operation of the process, is suggested.