The ability to predict the interfacial behavior of chemicals is important in many industrial operations. In oil and gas reservoirs, the effect of injected chemicals on interfacial tension, reservoir rock wettability and adsorption are all important factors to consider. Tools that allow the computational screening of a large number of candidate chemicals for a target application, lead to substantial time and cost savings. In this work quantum mechanical calculations within the COSMO (Conductor-like Screening Model) framework are used to predicting the interfacial behavior of pure compounds and mixtures. The procedure is validated by comparison to experimental data and applied to optimize the design of additives in the acid treatment of oil reservoirs.