title: DuraLith geopolymer waste form for Hanford secondary waste: correlating setting behavior to hydration heat evolution.
abstract: The binary furnace slag-metakaolin DuraLith geopolymer waste form, which has been considered as one of the candidate waste forms for immobilization of certain Hanford secondary wastes (HSW) from the vitrification of nuclear wastes at the Hanford Site, Washington, was extended to a ternary fly ash-furnace slag-metakaolin system to improve workability, reduce hydration heat, and evaluate high HSW waste loading. A concentrated HSW simulant, consisting of more than 20 chemicals with a sodium concentration of 5 mol/L, was employed to prepare the alkaline activating solution. Fly ash was incorporated at up to 60 wt% into the binder materials, whereas metakaolin was kept constant at 26 wt%. The fresh waste form pastes were subjected to isothermal calorimetry and setting time measurement, and the cured samples were further characterized by compressive strength and TCLP leach tests. This study has firstly established quantitative linear relationships between both initial and final setting times and hydration heat, which were never discovered in scientific literature for any cementitious waste form or geopolymeric material. The successful establishment of the correlations between setting times and hydration heat may make it possible to efficiently design and optimize cementitious waste forms and industrial wastes based geopolymers using limited testing results.
authors: Vitreous State Laboratory, The Catholic University of America, 620 Michigan Avenue NE, Washington, DC 20064, USA.
authors: Hui
authors: H
authors: Xu
authors: Vitreous State Laboratory, The Catholic University of America, 620 Michigan Avenue NE, Washington, DC 20064, USA. Electronic address: gongw@vsl.cua.edu.
authors: Weiliang
authors: W
authors: Gong
authors: Vitreous State Laboratory, The Catholic University of America, 620 Michigan Avenue NE, Washington, DC 20064, USA.
authors: Larry
authors: L
authors: Syltebo
authors: Vitreous State Laboratory, The Catholic University of America, 620 Michigan Avenue NE, Washington, DC 20064, USA.
authors: Werner
authors: W
authors: Lutze
authors: Vitreous State Laboratory, The Catholic University of America, 620 Michigan Avenue NE, Washington, DC 20064, USA.
authors: Ian L
authors: IL
authors: Pegg
mesh_terms: D019245:Compressive Strength; D006358:Hot Temperature; D008670:Metals / Q000032:analysis; D011108:Polymers / Q000737:chemistry; D011850:Radioactive Waste; D012037:Refuse Disposal / Q000379:methods*; D014861:Washington; D064091:Waste Disposal Facilities; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D008670:Metals; D011108:Polymers; D011850:Radioactive Waste; D014874:Water Pollutants, Chemical
keywords: DuraLith; Geopolymer waste form; Hanford secondary waste; Hydration heat; Setting time