Abstract Several pyrometallurgical industries encounter production losses due to the attachment of metallic droplets to solid particles in slags. Although scarce, due to experimental challenges, the available results indicate the importance of interfacial energies. Simulations based on a phase field model potentially circumvent this lack of experimental data and allow a more systematic insight into the observed phenomenon. In the present work, a phase field model for solid-liquid binary systems with spinodal decomposition in the liquid is implemented to simulate the metal droplet formation and growth in slags with non-reacting solid particles. The simulations allowed evaluating the influence of the interfacial energies and initial slag composition on the attachment of metallic droplets to solid particles as a function of time for four different regimes, namely no wettability of the metal on the particle, low wettability, high wettability and full wettability.