ChEMS Seminar: Capture of Tritiated Water and Radioactive Iodine from Spent Fuel Reprocessing Off-Gases by Solid Adsorbents

Friday, May 15, 2015 - 3:00 p.m. to Saturday, May 16, 2015 - 3:55 p.m.
McDonnell Douglas Engineering Auditorium (MDEA)
Prof. Lawrence L. Tavlarides
Department of Biomedical and Chemical Engineering
Syracuse University

The capture of radioactive off gases from spent nuclear fuel reprocessing plants is an important separation process in the treatment of nuclear fuels. Our Team has been engaged in the study of the adsorption phenomena of I2 and H2O on molecular sieve (MS) 3A and reduced silver mordenite (Ag0Z) to obtain adsorption data that are being employed in adsorption model development.  An overview of the modeling effort will be presented. Experimental methods used to obtain single layer pellet adsorption equilibrium data and transient uptake data of iodine and water will be described and data on MS 3A will be presented. The MS 3A equilibrium adsorption data were analyzed by the generalized statistical thermodynamic adsorption (GSTA) isotherm model. The results show that the GSTA isotherm model works very well to describe the equilibrium behavior of water adsorption on MS 3A. The best number of equilibrium parameters for the current experimental data was determined to be a set of four.  This result suggests that the sorbent crystals contain four distinct adsorption sites. Results of an analysis of the Linear Driving Force and Shrinking Core models to predict the transient water adsorption data will also be presented. In addition the  capability of the SKUA software which combines kernels to describe transient diffusion and adsorption in the pellet employed to describe the transient adsorption-desorption process of water on MS 3A will be shown. Current iodine adsorption studies on Ag0Z suggest that the best reduction conditions of silver mordenite are at 400 0C and 24 hours, the adsorption process of I2 is largely due to chemisorption, and equilibrium curves constructed for iodine adsorption on Ag0Z at 1500C also support the chemisorption process. Acquisition of these iodine adsorption data are still in progress and any forth coming analysis of the results will be presented.   

Bio: Lawrence L. Tavlarides is a professor of chemical engineering in the Department of Biomedical and Chemical Engineering at Syracuse University. He served as chair of the Chemical Engineering and Materials Science Department in 1981-85, Associate Dean of the College of Engineering (1995-1996), and was on the faculty in the Chemical Engineering Department at Illinois Institute of Technology (1969-1981). He leads an active research group in adsorption studies of gases from nuclear waste treatment and syntheses of biofuels from oils using supercritical fluid technology. His research activities also include mixing phenomena in liquid dispersions undergoing interfacial mass transfer with reaction, synthesis of adsorbents for heavy metal ions and rare earth elements separations, supercritical extraction of PCB’s from contaminated soils, and supercritical combustion of diesel fuel amongst others. He served as president and is a board member of the International Committee of Solvent Extraction.