SEARCH · Engineering Papers
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
LaCl3 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. La3+ is bonded in a 9-coordinate geometry to nine equivalent Cl1- atoms. There are six shorter (2.96 Å) and three longer (3.00 Å) La–Cl bond lengths. Cl1- is bonded in a trigonal non-coplanar geometry to three equivalent La3+ atoms.
Not Available
LaCl3N2Cl2 crystallizes in the orthorhombic Pnma space group. The structure is one-dimensional and consists of four nitrogen molecules; two Cl2 ribbons oriented in the (0, 1, 0) direction; and two LaCl3 ribbons oriented in the (1, 0, 0) direction. In each Cl2 ribbon, there are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 1-coordinate geometry to two equivalent Cl1- atoms. There are one shorter (2.02 Å) and one longer (2.91 Å) Cl–Cl bond lengths. In the second Cl1- site, Cl1- is bonded in a 1-coordinate geometry to two equivalent Cl1- atoms. In each LaCl3 ribbon, La3+ is bonded in a 5-coordinate geometry to five Cl1- atoms. There are a spread of La–Cl bond distances ranging from 2.63–2.88 Å. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a water-like geometry to two equivalent La3+ atoms. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one La3+ atom.
This paper discusses the effects of composition and canister centerline cooling (CCC) on the microstructures, phase distribution, and chemical durability of dehalogenated iron phosphate waste forms starting from chloride-based salt simulants including KCl (Simple-1), NdCl3 (Simple-2), SrCl2 (Simple-3), LaCl3 (Simple-4), LiCl (Simple-5), CsCl (Simple-6), as well as a complex simulant containing LiCl, KCl, NaCl, CsI, SrCl2, CeCl3, and NdCl3 called ERV2. The simulants represent salt constituents present in salt wastes from electrorefiners used for electrochemical reprocessing. These salts are reacted with ammonium dihydrogen phosphate (ADP) resulting in a NH4Cl (dechlorination) byproduct that is captured and phosphate product containing oxides of the salt cations. This product is further stabilized using Fe2O3 through vitrification at higher temperatures. The results presented herein describe the properties of CCC-treated materials following dechlorination and vitrification including phase identification and quantification, elemental distributions, and chemical durabilities. The chemical durability in the CCC-cooled samples are lower durability than quenched materials for the ERV2 samples. The phases formed upon CCC cooling are very complex compositionally and microstructurally.