The emission of off-gas streams from used fuel recycling is a concern in nuclear energy usage as they contain radioactive compounds, such as, 3H, 14C, 85Kr, 131I, and 129I that can be harmful to human health and environment. Radioactive iodine, 129I, is particularly troublesome as it has a half-life of more than 15 million years and is prone to accumulate in human thyroid glands. Organic iodides are hazardous even at very low concentrations, and hence the capture of 129I is extremely important. Dynamic adsorption experiments were conducted to determine the efficiency of sodium mordenite, partially exchanged silver mordenite, and fully exchanged silver mordenite for the removal of methyl iodide present at parts per billion concentrations in a simulated off-gas stream. Kinetic analysis of the system was conducted incorporating the effects of diffusion and mass transfer. The possible reaction mechanism is postulated and the order of the reaction and the values of the rate constants were determined from the experimental data. Adsorbent characterization is performed to investigate the nature of the adsorbent before and after iodine loading. This paper will offer a comprehensive understanding of the methyl iodide behavior when in contact with the mordenites.

1. Introduction
2. Materials and Method
    2.1 Synthesis of Silver-loaded Mordenite
    2.2 Experimental Setups and Procedures
3. Results and Discussion
    3.1 Experimental Setup 1
    3.2 Experimental Setup 2
    3.3 Summary of Continuous Adsorption Runs
4. Analysis and Characterization
    4.1 BET Surface Area Analysis
    4.2 Silver Content Determination in Mordenites
    4.3 Scanning Electron Microscopy (SEM)Imaging
    4.4 Energy Dispersive X-ray Spectroscopy(EDS)
    4.5 X-ray Diffraction Analysis (XRD)
5. Kinetics and Mass Transfer Analysis
    5.1 Reaction Mechanism
    5.2 Mass Transfer Dynamics
    5.3 Rate Controlling Mechanism
6. Conclusion
Acknowledgements
Appendix a

• Tejaswini Vaidya(University of Idaho, 875 Perimeter Dr, Moscow, ID 83844, United States)
• John P. Stanford(University of Idaho, 875 Perimeter Dr, Moscow, ID 83844, United States)
• Nicolene van Rooyen(University of Idaho, 875 Perimeter Dr, Moscow, ID 83844, United States)
• Krishnan Raja(University of Idaho, 875 Perimeter Dr, Moscow, ID 83844, United States)
• Vivek Utgikar(University of Idaho, 875 Perimeter Dr, Moscow, ID 83844, United States)
• Piyush Sabharwall(Idaho National Laboratory, 1955 N Fremont Ave, Idaho Falls, ID 83415, United States)