skip to main content

DOE PAGESDOE PAGES

Title: K 2x Sn 4-x S 8-x (x = 0.65–1): a new metal sulfide for rapid and selective removal of Cs + , Sr 2+ and UO 2 2+ ions

The fission of uranium produces radionuclides, 137Cs and 90Sr, which are major constituents of spent nuclear fuel. The half-life of 137Cs and 90Sr is nearly 30 years and thus that makes them harmful to human life and the environment. The selective removal of these radionuclides in the presence of high salt concentrations from industrial nuclear waste is necessary for safe storage. We report the synthesis and crystal structure of K 2xSn 4-xS 8-x (x = 0.65–1, KTS-3) a material which exhibits excellent Cs +, Sr 2+ and UO 2 2+ ion exchange properties in varying conditions. Furthermore, the compound adopts a layered structure which consists of exchangeable potassium ions sandwiched between infinite layers of octahedral and tetrahedral tin centers. K 2xSn 4-xS 8-x (x = 0.65–1, KTS-3) crystallizes in the monoclinic space group P2 1/c with cell parameters a = 13.092(3) Å, b = 16.882(2) Å, c = 7.375(1) Å and β = 98.10(1)°. Refinement of the single crystal diffraction data revealed the presence of Sn vacancies in the tetrahedra that are long range ordered. The interlayer potassium ions of KTS-3 can be exchanged for Cs +, Sr 2+ and UO 2 2+. KTS-3 exhibits rapid and efficient ion exchangemore » behavior in a broad pH range. The distribution coefficients (K d) for KTS-3 are high for Cs + (5.5 × 10 4), Sr 2+ (3.9 × 10 5) and UO 2 2+ (2.7 × 10 4) at neutral pH (7.4, 6.9, 5.7 ppm Cs +, Sr 2+ and UO 2 2+, respectively; V/m ~ 1000 mL g -1). KTS-3 exhibits impressive Cs +, Sr 2+ and UO 2 2+ ion exchange properties in high salt concentration and over a broad pH range, which coupled with the low cost, environmentally friendly nature and facile synthesis underscores its potential in treating nuclear waste.« less
Authors:
 [1] ;  [1] ;  [1] ;  [1] ;  [2]
  1. Northwestern Univ., Evanston, IL (United States)
  2. Northwestern Univ., Evanston, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States). Materials Science Division
Publication Date:
Grant/Contract Number:
AC02-06CH11357; DMR-1410169
Type:
Accepted Manuscript
Journal Name:
Chemical Science
Additional Journal Information:
Journal Volume: 7; Journal Issue: 2; Journal ID: ISSN 2041-6520
Publisher:
Royal Society of Chemistry
Research Org:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org:
USDOE Office of Nuclear Energy (NE); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); National Science Foundation (NSF)
Country of Publication:
United States
Language:
English
Subject:
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; 11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
OSTI Identifier:
1352636