FUEL SYSTEM ICING INHIBITORS - THE SYNTHESIS OF ESTERS OF OXAACIDS

Currently ethylene glycol mono methyl ether (EGME) and diethylene glyc ol mono methyl ether (DiEGME) are used as fuel system icing inhibitor additives in both military and commercial aircraft. These compounds ar e toxic at the concentrations that required for effective deicing. Whe n fuel systems sumps, filters and storage tanks are drained, they cont ain EGME/DiEGME and create hazards for personnel. Ethyl esters synthes ized from oxaacids have been identified as possible fuel system icing inhibitor additive replacements. These compounds were synthesized from oxaacids and ethanol by an acid catalyzed Fischer esterfication metho d. The products were identified by infrared spectrometry, nuclear magn etic resonance spectrometry, and elemental analysis. Physical characte rization included boiling point determination and refractive index. Th e tested oxaesters were found to be fuel stable for at least two years by accelerated storage tests. Octanol-water partition coefficients we re determined and indicate the compounds have a higher solubility in f uel than in water. These oxaesters are predicted to be non-toxic.