TY - JOUR
T1 - Synthesis of nitrate sodalite
T2 - An in situ scanning calorimetric study
AU - Liu, Qingyuan
AU - Navrotsky, Alexandra
N1 - Funding Information:
The authors thank Dr. Carlos F. Jove-Colon and Dr. Francois R. Bonhomme for suggestions on some of the syntheses. We appreciate comments from Richard Wirth, Guy Hovis, Associate Editor Kelly Russell, and an anonymous reviewer. This work was supported by DOE Grant DE FG07 01ER63298.
PY - 2007/4/15
Y1 - 2007/4/15
N2 - The formation of nitrate sodalite, an important constituent of the resilient heels at DOE nuclear waste storage sites, was closely followed by oven synthesis, in situ calorimetry as a function of heating rate from 0.01 to 0.1 °C/min and X-ray diffraction. A transition sequence of amorphous-zeolite A-sodalite-cancrinite was confirmed. For in situ synthesis calorimetry, the heat flow peaks related to zeolite A formation are shifted to higher temperatures as heating rate increases. Although the end products are mostly nitrate sodalite, no calorimetric signals associated with zeolite A to sodalite conversion are detected. This suggests that the enthalpy of formation of zeolite A and sodalite are very similar and the zeolite A to sodalite conversion enthalpy is small. This conclusion is in accord with previous measurements by oxide melt solution calorimetry.
AB - The formation of nitrate sodalite, an important constituent of the resilient heels at DOE nuclear waste storage sites, was closely followed by oven synthesis, in situ calorimetry as a function of heating rate from 0.01 to 0.1 °C/min and X-ray diffraction. A transition sequence of amorphous-zeolite A-sodalite-cancrinite was confirmed. For in situ synthesis calorimetry, the heat flow peaks related to zeolite A formation are shifted to higher temperatures as heating rate increases. Although the end products are mostly nitrate sodalite, no calorimetric signals associated with zeolite A to sodalite conversion are detected. This suggests that the enthalpy of formation of zeolite A and sodalite are very similar and the zeolite A to sodalite conversion enthalpy is small. This conclusion is in accord with previous measurements by oxide melt solution calorimetry.
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U2 - 10.1016/j.gca.2007.01.011
DO - 10.1016/j.gca.2007.01.011
M3 - Article
AN - SCOPUS:34047129163
SN - 0016-7037
VL - 71
SP - 2072
EP - 2078
JO - Geochimica et Cosmochimica Acta
JF - Geochimica et Cosmochimica Acta
IS - 8
ER -