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Title: Synthesis and characterization of iodosodalite

Abstract

The effects of six process variables on the hydrothermal growth of iodosodalite, Na8Al6Si6O24I2, were investigated: pH (NaOH concentration), aging time, temperature, Al/Si ratio, the precursors used (i.e., zeolite 4A, kaolinite, meta-kaolin, colloidal silica, and sodium aluminate), and precursor concentration. Powder X-ray diffraction (XRD) was performed to identify phases and Rietveld refinements were used to quantify mass fractions of phases. Iodosodalite yield increased as aging time and pH increased. The crystallization of iodosodalite was favored in the temperature range 140-180 °C whereas, at 200 °C, basic cancrinite formed at the expense of some iodosodalite. Decreasing the Al/Si ratio by half increased the crystallization of basic cancrinite. Lowering the precursor concentration by adding water revealed the crystallization of nepheline hydrate I and a decrease in the sodalite fraction. Among the tested precursors, zeolite 4A yielded the highest mass fraction of iodosodalite in the synthesized powders. From the aging time and temperature variation experiments, the phase transformation of zeolite A → sodalite → cancrinite was observed. The crystallization of various minerals suggests that mechanisms for transport of the ions and formation of the aluminosilicate frameworks vary with hydrothermal conditions.

Authors:
 [1];  [2];  [3];  [4];  [5]
  1. Materials Science and Engineering Program, Washington State University, Pullman Washington
  2. School of Chemical Engineering and Bioengineering, Washington State University, Pullman Washington; Pacific Northwest National Laboratory, Richland Washington
  3. School of Mechanical and Materials Engineering, Washington State University, Pullman Washington
  4. Materials Science and Engineering Program, Washington State University, Pullman Washington; Pacific Northwest National Laboratory, Richland Washington
  5. Materials Science and Engineering Program, Washington State University, Pullman Washington; Pacific Northwest National Laboratory, Richland Washington; School of Mechanical and Materials Engineering, Washington State University, Pullman Washington
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1363988
Report Number(s):
PNNL-SA-119593
Journal ID: ISSN 0002-7820; 830403000
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of the American Ceramic Society; Journal Volume: 100; Journal Issue: 5
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Iodosodalite; Hydrothermal; XRD; Zeolite; sodalite

Citation Formats

Chong, Saehwa, Peterson, Jacob, Nam, Junghune, Riley, Brian, and McCloy, John. Synthesis and characterization of iodosodalite. United States: N. p., 2017. Web. doi:10.1111/jace.14772.
Chong, Saehwa, Peterson, Jacob, Nam, Junghune, Riley, Brian, & McCloy, John. Synthesis and characterization of iodosodalite. United States. doi:10.1111/jace.14772.
Chong, Saehwa, Peterson, Jacob, Nam, Junghune, Riley, Brian, and McCloy, John. Tue . "Synthesis and characterization of iodosodalite". United States. doi:10.1111/jace.14772.
@article{osti_1363988,
title = {Synthesis and characterization of iodosodalite},
author = {Chong, Saehwa and Peterson, Jacob and Nam, Junghune and Riley, Brian and McCloy, John},
abstractNote = {The effects of six process variables on the hydrothermal growth of iodosodalite, Na8Al6Si6O24I2, were investigated: pH (NaOH concentration), aging time, temperature, Al/Si ratio, the precursors used (i.e., zeolite 4A, kaolinite, meta-kaolin, colloidal silica, and sodium aluminate), and precursor concentration. Powder X-ray diffraction (XRD) was performed to identify phases and Rietveld refinements were used to quantify mass fractions of phases. Iodosodalite yield increased as aging time and pH increased. The crystallization of iodosodalite was favored in the temperature range 140-180 °C whereas, at 200 °C, basic cancrinite formed at the expense of some iodosodalite. Decreasing the Al/Si ratio by half increased the crystallization of basic cancrinite. Lowering the precursor concentration by adding water revealed the crystallization of nepheline hydrate I and a decrease in the sodalite fraction. Among the tested precursors, zeolite 4A yielded the highest mass fraction of iodosodalite in the synthesized powders. From the aging time and temperature variation experiments, the phase transformation of zeolite A → sodalite → cancrinite was observed. The crystallization of various minerals suggests that mechanisms for transport of the ions and formation of the aluminosilicate frameworks vary with hydrothermal conditions.},
doi = {10.1111/jace.14772},
journal = {Journal of the American Ceramic Society},
number = 5,
volume = 100,
place = {United States},
year = {Tue Mar 07 00:00:00 EST 2017},
month = {Tue Mar 07 00:00:00 EST 2017}
}
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