Portable Analysis of MDA in Jet Fuel using Capillary Scale Liquid Chromatography

Metal Deactivator Additive (MDA) is a chelating agent (typically N,N’-disalicylidene-1,2-propanediamine) that is often added to jet fuels to prevent metal ions, primarily trace copper, from catalyzing reactions (i.e., oxidation and thermal breakdown of the fuel) that reduce fuel efficiency and foul engine components. Fuel supplies are tested regularly to ensure MDA is present at appropriate concentration (i.e., not too much or too little) to prevent fouling; however, timely testing at critical locations outside the laboratory can prove difficult. Often, fuel samples are collected and shipped to an offsite laboratory causing lead times of several days between sampling and analysis, putting fuel use on hold. The Axcend Focus LC is a compact and portable capillary scale liquid chromatograph (LC) that is capable of onsite analysis of MDA in jet fuel down to the recommended cutoff threshold of 5.7 mg/L as established by ASTM D1655. This allows for portable, on-site MDA analysis in approximately 10 minutes, consuming only 63 µL of solvent and fuel per sample. ASTM has approved this method in D8545 as the only portable LC method for MDA analysis. In this poster, the separation conditions, accuracy, and linearity of MDA analysis by capillary LC are presented.