This contribution provides a model-based approach of a nonspecific emulsion-assisted precipitation process in order to analyze the influence of process parameters on the particle size and size distribution of primary nanoparticles. The here presented process route comprises mass transfer of reactant molecules from the continuous phase of the emulsion into the dispersed droplets in a stirred tank reactor. In a time scale analysis, the penetration of the reactant through the surfactant-laden interface can be identified as the controlling process mechanism. With regard to the rate-controlling process step, a mathematical model based on the population balance approach is derived. A high resolution discretization scheme extended by a flux limiter function is applied to solve the population balance equations. The dynamics of the particle formation process and the final particle size distribution are investigated in numerical simulations by variations of the droplet size, the initial concentration level of the dissolved reactant in the droplet, and the feeding rate into the reactor. It has been figured out that an increase in the feeding rate and a decrease in the emulsion droplet diameter results in a reduction of the mean particle size. In contrast, low feeding rates and large droplets are favorable to obtaining homogeneous reaction conditions in the stirred tank reactor.