| Scanning electron microscopes (SEMs) are widely used to provide three-dimensional information about the morphology and distribution of components on the surfaces of soil specimens. The transport of 2,4,6-Trinitrotoluene in soils has been found to be influenced by a number of environmental factors, such as, temperature and water content. In this work, we used a scanning electron microscope coupled with energy-dispersed X-ray (EDS) to study and describe the distribution of TNT on soil surfaces as a function of time. X-ray dot mapping was used to analyze carbon and nitrogen on surface of mixing TNT/sand on microscopic scale by comparing scanning electron microscope image of the same areas of soil samples after four days. The images obtained from SEM showed differences in the morphology and spatial distribution of the explosive on sand after sample preparation. On the other hand, EDS measurements showed a decrease in the nitrogen fluorescence signal as well as in the carbon fluorescence signal, demonstrating the movement of TNT during the time. The kinetics of surface sublimation and the kinetics of TNT through the sand were studied. According to experimental results, two theoretical models incorporate parametric equations to explain nonlinear sublimation rate of TNT on sand and diffusion rate of solid TNT through to sand surface. |
