Facile synthesis of novel Bi-SBA-15 adsorbents by an improved impregnation reduction method for highly efficient capture of iodine gas.

Development of high efficient adsorbents to capture iodine is of great significance for the active development of nuclear power. Herein, Bi-SBA-15 was firstly synthesized and applied for capture of iodine gas. Bi-SBA-15 materials were prepared by an improved impregnation reduction method. The benefit of this method was that the Bi nanoparticles with flocculent and spherical morphologies were loaded on the surface of SBA-15, which provide abundant active sites for iodine and improve the utilization rate of active sites, so as to attain a record high capture capacity (up to 925 mg/g within 60 min) and high stablitiy (91.2%) at 200 °C. The results demonstrated that the loading of Bi on the surface showed a significant impact on the structure of Bi-SBA-15 and did greatly enhance the iodine capture. Furthermore, the high iodine capture capacity mainly derived from the chemical adsorption in the stable form of BiI. The obtained Bi-SBA-15 materials exhibited excellent aqueous and irradiation stability. Thus, the results indicated that the new and highly efficient Bi-SBA-15 was a potential radioactive iodine gas capture material.