Activated Carbon Impregnated by Hexamethylene Tetramine for Localization of CH₃I

Triethylene diamine （TEDA）—a widely used impregnant for localization of iodine, possesses a few drawbacks, such as high steam pressure and low flash point, which restricts that activated carbon (AC) impregnated by TEDA can be only used below 390 K. Hexamethylene tetramine （HMTA） could be a substitute for TEDA because of its high flash point and low volatility. The impacts of a few parameters in the process of locating iodine by AC containing HMTA at 27℃ and 95%-96.5%(RH%) were tested. It is shown that appropriate quantity of impregnant （5%）and drying time （30min） can improve the adsorption efficiency, whereas the decrease of pH and exposure to air of AC play the negative role. These preliminary results provide some experimental basis for further study of HMTA as impregnant for location of radioactive iodine.