Modeling gas phase of enthalpy and entropy of adsorption and de- sorption of Ln[Hfac]x compounds

The threat that a terrorist organization might attack the United States is a realistic concern that the National Nuclear Security Administration and other government agencies must consider. In the case that a nuclear weapon is detonated , the amount of time required to analyze the post-detonation debris and materials is crucial ,therefore, if more efficient methods of analyzing these materials can be developed then the faster the threat can be opposed and neutralized. In order to expedite the analysis of the fall out debris, a gas chromatography (GC) system will be used to start the separation process. Then a temperature controlled interface will be machined that will link the gas chromatography system to a time of flight mass spectrometer. By interfacing these two systems, the amount of time required for analysis will be decreased, and the amount of material required for analysis will also be reduced. To insure that this method will be fast, efficient, and accurate, a computer model of the system will be created using both the Matlab and C++ computer codes. This program will model the rate of adsorption and de-sorption of different lanthanide compounds along the quartz column of the gas chromatography system. By using Monte-Carlo analysis, the model will calculate enthalpy and entropy created in the column by the different lanthanide compounds. This model will be validated by actual experimental data that is collected in the Radiochemistry Center of Excellence currently located at the University of Tennessee, Knoxville (UTK).