title: Volatility and leachability of heavy metals and radionuclides in thermally treated HEPA filter media generated from nuclear facilities.
abstract: The purpose of the present study was to apply thermal treatments to reduce the volume of HEPA filter media and to investigate the volatility and leachability of heavy metals and radionuclides during thermal treatment. HEPA filter media were transformed to glassy bulk material by thermal treatment at 900°C for 2h. The most abundant heavy metal in the HEPA filter media was Zn, followed by Sr, Pb and Cr, and the main radionuclide was Cs-137. The volatility tests showed that the heavy metals and radionuclides in radioactive HEPA filter media were not volatilized during the thermal treatment. PCT tests indicated that the leachability of heavy metals and radionuclides was relatively low compared to those of other glasses. XRD results showed that Zn and Cs reacted with HEPA filter media and were transformed into crystalline willemite (ZnO·SiO(2)) and pollucite (Cs(2)OAl(2)O(3)4SiO(2)), which are not volatile or leachable. The proposed technique for the volume reduction and transformation of radioactive HEPA filter media into glassy bulk material is a simple and energy efficient procedure without additives that can be performed at relatively low temperature compared with conventional vitrification process.
authors.affiliation: Korea Atomic Energy Research Institute (KAERI), Yuseong-gu, Daejeon, Republic of Korea.
authors.forename: In-Ho
authors.initials: IH
authors.lastname: Yoon
authors.forename: Wang-Kyu
authors.initials: WK
authors.lastname: Choi
authors.forename: Suk-Chol
authors.initials: SC
authors.lastname: Lee
authors.forename: Byung-Youn
authors.initials: BY
authors.lastname: Min
authors.forename: Hee-Chul
authors.initials: HC
authors.lastname: Yang
authors.forename: Kune-Woo
authors.initials: KW
authors.lastname: Lee
mesh_terms: D008567:Membranes, Artificial; D019216:Metals, Heavy / Q000737:chemistry* / Q000302:isolation & purification; D055848:Nuclear Power Plants; D011868:Radioisotopes / Q000737:chemistry* / Q000302:isolation & purification; D014835:Volatilization; D014961:X-Ray Diffraction
chemical_list: D008567:Membranes, Artificial; D019216:Metals, Heavy; D011868:Radioisotopes