Prediction of minimum flash point behavior for binary mixtures: Fid-Bau Portal

Prediction of minimum flash point behavior for binary mixtures

Vidal, M. / Mannan, M.S. / Rogers, W.J.

Flash point is a primary property used to determine the fire and explosion hazards of a liquid. Minimum flash point behavior (MFPB) is exhibited when the flash point of a mixture is below the flash points of the individual components. The identification of this behavior is critical, because a hazardous situation results from taking the lowest component flash point value as the mixture flash point. Experimental tests for the complete composition range of a mixture are time consuming, whereas a mixture flash point can be estimated using a computational method and available information. From the infinite dilution activity coefficients of the mixture components, the potential of the liquid mixture to exhibit MFPB can be identified. These coefficients represent the molecular interactions, which affect the vapor pressure of the mixture and consequently its flash point value. COSMO-RS is used to estimate infinite dilution activity coefficients, and then these parameters are used in a procedure that identify if the mixture will exhibit MFPB or if the flash point value for the mixture will be between the values of the individuals components of the mixture. The purpose of this work is to develop a procedure to predict binary mixture flash points from available information and to study estimation techniques that can be applied when the needed parameters and/or experimental data are not available. The ultimate goal is to predict MFPB even when the experimental data available are limited. The UNIFAC model is used in the prediction of mixtures exhibiting MFPB. The incorporation of quantum chemical calculations and its usefulness in the prediction of mixture flash points is also discussed.