Dissolved water in jet fuels: a low-temperature quality and water solubility study

While undesirable, water contamination of jet fuels is unavoidable. It is essential to understand the impacts of dissolved water on the fuel properties and the water-fuel interactions. In this study, the impacts of dissolved water on low-temperature qualities of aviation fuels were determined. The liquid-solid phase transition temperature was found to increase with the jet fuels saturated with dissolved water under increased temperatures owing to the increase of fuel water solubility. The conductor-like screening model for realistic solvation (COSMORS) method was employed to predict the water solubility in petroleum and sustainable aviation fuels (PAFs and SAFs) over a temperature range of -40 to 50 degrees C based on fuel composition data obtained by comprehensive GC x GC chromatography. The calculation results are in good agreement with experimental values at temperatures below 20 degrees C, with RMSE = 17.1 and 17.7 ppm for PAFs and SAFs, respectively. Results calculated for these complex fuel chemistries predicted experimental values more closely than calculations performed for simpler PAF and SAF surrogates. COSMO-RS was also employed to calculate water solubility in PAF and SAF blends (RMSE = 18.3 ppm). Results demonstrate that the COSMO-RS method has potential as a tool in new SAF certification.