Development of Assay Methods for Liquid Propellants

摘要

A feasibility study determined that mobile phase ion chromatography (MPIC) and high performance ion chromatography, (HPLC) can identify and quantify the components of a liquid propellant. MPIC used a Dionex ion chromatograph equipped with a cation fiber suppressor and electrochemical and conductivity detectors in series. Sharp peaks were detected for the hydroxylamine and triethanolamine in LP 1845. In this sample, 252.7 ppm hydroxylammonium nitrate (86.9 ppm as free hydroxylamine) and 79.8 ppm triethanolammonium nitrate (56.1 pm as free triethanolamine), were detected. Hexanesulfonic acid was used as the eluent in this MPIC separation. Tw different mobile phase systems were found suitable for the liquid propellant separation of NOS-365 and LP 1845 by HPIC. For NOS-365, an acetonitrile/water (5:95), 0.01M in octanesulfonic acid at a pH 3.1 and a flow rate of 2.0 ml/min. eluted hydroxylammonium nitrate (HAN) at 4.8 minutes and isopropylammonium nitrate (IPAN) at 7.0 min. An acetonitrille/water (10:90), 0.005M in octanesulfonic acid at a flow rate of 2.0 ml/min. was used for LP 1845 to elute HAN at 5.3 min., triethanolammonium nitrate (TEAN) at 4.8 min., and IPAN at 14.0 min. Before quantification of these separations can be meaningful, optimization of the systems and creation of standard curves will have to be established. Keywords: Octane sulfonic acid; Acetonitrile; Chromatogram; Dionex ion chromatography.