Asphaltene precipitation is driven by self-association of asphaltene molecules to form nanoaggregates and subsequent formation of clusters from nanoaggregates (Mullins, O. C. Energy Fuels 2010, 24 (4), 2179-2207). Recently, a novel thermodynamic framework was proposed for the onset of asphaltene nanoaggregation in binary solvents with a functional group-based UNIFAC model (Wang, M., et al. AIChE J. 2016, 62 (4), 1254-1264). In this work, a computational chemistry-based COSMO-SAC model is applied with the aggregation thermodynamics to predict asphaltene precipitation. The predictions are further improved with the use of apparent sigma profiles based on the conceptual segment approach (Islam, M. R., Chen, C.-C. Ind. Eng. Chem. Res. 2015, 54 (16), 4441-4454).