Chromatographic Determination of Trace Amounts of HMX, RDX and TNT Compounds in Water Samples after Cloud Point Extraction

Explosive compounds are known to release a significant plume containing toxic levels (μgL-1 to mgL-1 range) and environmental pollution of military munitions sites are hazardous to agricultural crops and humans. HMX, RDX and TNT are major ingredients in nearly every ammunition formulation and are the secondary explosives used in greatest quantities. Since the explosives are found at ultra trace levels in environment samples, so priorto their determination an enrichment process is required and afterwards rapid and sensitive techniques for their monitoring are needed. In this work, an analytical method was developed to the preconcentration of the explosive compounds (HMX,RDX and TNT) in water samples based on the cloud point extraction, and after extraction, the extracted compounds were analysed by high performance liquid chromatography. The parameters affecting extraction efficiency (such as concentrations of Triton X-114 and Cetyl-trimethylammonium bromide, electrolyte and its amount, temperature, incubation time, and centrifuge time) and chromatographic conditions (such as selected wavelength, nature of mobile phase and gradient program) were evaluated and optimized. Under the optimum conditions, the improvement factors of 34, 29, 61 and detection limits of 0.1, 0.14, and 0.08 μgL−1 were obtained for HMX, RDX and TNT respectively. This method was successfully applied for the determination oftrace amounts of these compounds in water samples.