  We undertake a detailed numerical study of the {\it Active Model B} proposed
by Wittkowski et al. [Nature Comm. {\bf 5}, 4351 (2014)]. We find that the
introduction of activity has a drastic effect on the ordering kinetics. First,
the domain growth law shows a crossover from the usual Lifshitz-Slyozov growth
law for phase separation ($L \sim t^{1/3}$, where $t$ is the time) to a novel
growth law ($L \sim t^{1/4}$) at late times. Second, the correlation function
exhibits dynamical scaling for a given activity strength $\lambda$, but the
scaling function depends on $\lambda$.
