STUDIES OF RDX INTERACTIONS IN SOIL

Knowledge of the chemical state of explosive materials on soil surfaces is central to our understanding of the environmental effects of landmines as well as to employ existing technologies for landmine sensing. We used X ray photoelectron spectroscopy to study the surface chemistry of TNT and RDX on soil substrate surfaces as a function of soil pH. These explosives exists in many forms in the solid state. At least two forms have been reported for RDX and TNT in the solid state. Different forms are observed for both TNT and RDX adsorbed on soil substrate surfaces. These forms have a markedly different morphology than the one observed on flat surfaces and are found to be pH sensitive. The N 1s binding energy is found to be markedly different for TNT and RDX adsorbed on soil particles as compared to the one measured for these chemicals on other surfaces. The results are consistent with a change in the chemical state of the explosive upon its interaction with soil particles.