TY - JOUR
T1 - Nitrate cancrinite
T2 - Synthesis, characterization, and determination of the enthalpy of formation
AU - Liu, Qingyuan
AU - Xu, Hongwu
AU - Navrotsky, Alexandra
N1 - Funding Information:
We thank Dr. Sergey Ushakov for the TEM analysis. We acknowledge the National Center for Electron Microscopy at the Lawrence Berkeley National Laboratory for the use of its facilities. We also thank Dr. Carlos F. Jove-Colon at the Sandia National Laboratories for valuable discussions. We appreciate the assistance of Gregory Baxter in electron microprobe analysis. This work was supported by DOE Grant DE FG07 01ER63298.
PY - 2005/12/27
Y1 - 2005/12/27
N2 - Nitrate cancrinite, with an ideal formula of Na8[Al 6Si6O24](NO3)2 • 4H2O, is an important constituent of high-level nuclear wastes at several US Department of Energy (DOE) storage sites. A simple synthesis route for this material is described. Pure nitrate cancrinite has been prepared using a mixed solution of sodium silicate, sodium aluminate, sodium nitrate, and sodium hydroxide. Crystallization took place rapidly at 90 °C and the cancrinite phase emerged within a few hours of aging. Both X-ray diffraction and composition analyses indicated the formation of pure nitrate cancrinite. Solution calorimetric measurements of this material were performed with a Calvet-type calorimeter operated at 701 °C using molten lead borate (2PbO • B2O3) as the solvent. Enthalpies of formation from the constituent oxides and from the elements are -903.3 ± 15.7 kJ/mol and -14,258.3 ± 17.3 kJ/mol, respectively, for a sample with the analyzed formula of Na7.282[Al5.854Si6.146O 24](NO3)1.336(CO3)0.046 • 3.365H2O.
AB - Nitrate cancrinite, with an ideal formula of Na8[Al 6Si6O24](NO3)2 • 4H2O, is an important constituent of high-level nuclear wastes at several US Department of Energy (DOE) storage sites. A simple synthesis route for this material is described. Pure nitrate cancrinite has been prepared using a mixed solution of sodium silicate, sodium aluminate, sodium nitrate, and sodium hydroxide. Crystallization took place rapidly at 90 °C and the cancrinite phase emerged within a few hours of aging. Both X-ray diffraction and composition analyses indicated the formation of pure nitrate cancrinite. Solution calorimetric measurements of this material were performed with a Calvet-type calorimeter operated at 701 °C using molten lead borate (2PbO • B2O3) as the solvent. Enthalpies of formation from the constituent oxides and from the elements are -903.3 ± 15.7 kJ/mol and -14,258.3 ± 17.3 kJ/mol, respectively, for a sample with the analyzed formula of Na7.282[Al5.854Si6.146O 24](NO3)1.336(CO3)0.046 • 3.365H2O.
KW - Enthalpy of formation
KW - Nitrate cancrinite
KW - Nuclear waste
KW - Synthesis
KW - Thermodynamics
KW - Zeolite
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U2 - 10.1016/j.micromeso.2005.08.008
DO - 10.1016/j.micromeso.2005.08.008
M3 - Article
AN - SCOPUS:27944474804
SN - 1387-1811
VL - 87
SP - 146
EP - 152
JO - Microporous and Mesoporous Materials
JF - Microporous and Mesoporous Materials
IS - 2
ER -