Study on iodine adsorption capacity and adsorption mechanism of AgY

To systematically study the methyl iodide (CH3I) adsorption performance and adsorption mechanism of Ag ion exchange NaY zeolite (AgY), AgY adsorbents with different Ag content were selected. 16.6% AgY was capable of storing 150 mg/g and 275 mg/g of CH3I when the penetrated CH3I reached 1‰ and 100% inlet concentration. TEM and EDS results presented a high relationship between Ag dispersion and CH3I adsorption capability. The formation of a stable AgI complex rationalized the CH3I adsorption mechanism on AgY. Compared to AgX, AgY was verified to possess a strong acid resistance by FT-IR, SEM and XRD. The effect of three key parameters (temperature, humidity and gas velocity) on CH3I adsorption was carefully investigated by orthogonal experiment design. The experimental results showed that AgY had better iodine removal performance at a high temperature, low humidity, and low flow rate. This work provides technical reference for further engineering applications of 16.6%AgY in spent fuel reprocessing plants.