LAUSR

Abstract As interest in biofuel blends has grown through the years, especially in terms of jet fuel blend development, it has become more and more important to be aware of their physical chemical properties. One of them is the Flash Point (FP), which is intimately related to the flammability of the blend. With this in mind, the aim of this study was to determine experimentally and also mathematically new FP data on binary and ternary solutions containing ethanol, fatty acid ethyl esters (FAEE), and dodecane, as a way of providing data for flammability evaluation of jet fuels based on surrogates. Therefore, FPs of seventeen binary systems and eight ternary systems were measured. A vapor pressure approach was employed to FP prediction with NRTL and original UNIFAC activity coefficient models in order to further analyze flammability in terms of solution behavior, while providing guidance for FP prediction of these systems, needed for fuel development. NRTL binary interaction parameters were adjusted from FP data, as these parameters are not available in the literature for FAEE multicomponent systems. It was observed that addition of ethanol to dodecane or FAEEs steeply decreases FP. On the other hand, addition of FAEEs to dodecane does not affect FP as drastically, which implies an almost ideal behavior for these systems. Both the original UNIFAC and NRTL models were able to improve FP prediction in comparison to the ideal model for all ternary systems with RMSDs ranging from 4.6 K to 0.5 K and 1.3 K to 0.3 K respectively, which points to the validity of the adjusted NRTL parameters.