Fumed silica-Ce 기조 겔 화학제염제의 점성 및 고착성 핵종 제염특성

Rheological & Fixed Co/Cs Removal Behaviors of Fumed Silica-Ce Based Chemical Gel

The objective of this study is to develop the chemical decontamination gel that have a higher removal efficiency for radionuclides and produce less waste resulting from the decontamination. For this purpose, decontamination behaviors for Co-60 and Cs-137 radionuclides at surfaces of stainless-steel 304 and the rheological properties of chemical decontamination gel were investigated. Chemical decontamination gel was prepared by adding the gelling agents composed of a viscosifier and coviscosifier into the chemical decontamination agents of a 0.5M ammonium cerium nitrate solution dissolved in a 2M nitric acid. The chemical gelling agents were optimized as follows: a 6 wt.% of solution of fumed silica(Cab-O-Sil, M5) as the viscosifier and a 0.5 wt.% of solution of tripropylene glycol dodecyl ether (TPGDDE) or tripropylene glycol butyl ether (TPGBE) as coviscosifier. The proposed formulations for chemical decontamination gel provide an effective thixotropic prooerty which is defined as a decrese in viscosity with time under shear stress and followed by recovery of viscosity at rest, and high removal efficiency of above 90% for Co-60 and Cs-137.