Supercritical Fluid Chromatography for the Analysis of Nitroaromatics, Nitramines and Nitrate Esters

Abstract : A supercritical fluid chromatographic (SFC) system equipped with a capillary column and a thermionic ionization detector (TID) was evaluated as a potential analytical tool for the simultaneous determination of nitroaromatics, nitramines and nitrate esters. Examination of several stationary phases and modified fluids was carried out while determining optimal conditions for a suitable separation. The results indicate that a cyanopropyl stationary phase is best suited for these analytes, but the available percentages of cyanopropyl in the phase (i.e. 25% and 50%) do not give total resolution. The performance and usability of the TID was evaluated. Detection limits are estimated to be several times greater than those for standard HPLC and GC methods. Also, the usability and performance of the SFC were compared with HPLC and GC. SFC-TID can be used for the simultaneous determination of nitroaromatic, nitramines and nitrate esters, but current column and detection capability limitations greatly reduce its potential.