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The Application of X-Ray Diffraction at Elevated Temperatures to Study the Mechanism of Formation of Sodium Tripolyphosphate

Published online by Cambridge University Press:  06 March 2019

E. L. Moore  and
J. S. Metcalf
E. L. Moore
Affiliation:
Monsanto Chemical Company, St. Louis, Missouri
J. S. Metcalf
Affiliation:
Monsanto Chemical Company, St. Louis, Missouri
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Abstract

High-temperature X-ray diffraction techniques were employed to study the condensation reactions which occur when sodium orthophosphates are heated to 380°C. Crystalline Na4P2O7 and an amorphous phase were formed first from an equimolar mixture of Na2HPO4·NaH2PO4 and Na2HPO4 at temperatures above 150°C. Further heating resulted in the formation of Na5P3O10-I (high-temperature form) at the expense of the crystalline Na4P4O7 and amorphous phase. Crystalline Na5P3O10-II (low-temperature form) appears after Na5P3O10-I.

Conditions which affect the yield of crystalline Na4P2O7 and amorphous phase as intermediates and their effect on the yield of Na5P3O10 are also presented.

Type
Research Article
Information
Advances in X-Ray Analysis , Volume 5: Tenth Annual Conference on Applications of X-ray Analysis, August 7-9, 1961 , 1961 , pp. 276 - 284
Copyright
Copyright © International Centre for Diffraction Data 1961

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References

1. Topley, B., “The Condensed Phosphates,” Quart. Revs. (London), Vol. III, No. 4, 1949, p. 345.Google Scholar
2. Partridge, E. P., Hicks, V., and Smith, G. W., “A Thermal Microscopic and X-Ray Study of the System NaPO3-Na4P2O7,” J. Am. Ghem. Soc, 63, 1941, p. 454.Google Scholar
3. Andress, K. R. and Wüst, K., “Sodium Polyphosphates,” Z. anorg. u. allgem, Chem., Vol. 237, 1938, p. 113.Google Scholar
4. Morey, G. W., “The Transition Between Low and the High-Temperature Form of Sodium Tripolyphosphate,” J. Am. Chem. Soc., 80, 1958, p. 775.Google Scholar
5.Unpublished Monsanto data.Google Scholar
6. Windrow, B. and Kobe, K., “The System Sodium Oxide-Phosphorus Pentoxide-Water,” Ind. Eng. Chem., Vol. 44, 1952, p. 1439.Google Scholar
7. Edwards, J. W. and Herzog, A. H., “The Mechanism of Formation of Sodium Triphosphate and Ortho-phosphate Mixtures,” J. Am. Chem. Soc. 79, 1957, p. 3647.Google Scholar
8. Van Wazer, J. R., Griffith, E. J., and McCulIough, J. F., “Automatic pH Titratton of Soluble Phosphates and Their Mixtures,” Anal. Chem., Vol. 26, 1954, p. 1755.Google Scholar
9. Kolloff, R. H., “Analysis of Commercial Sodium Tripolyphosphate by Reverse Flow Ion Exchange Chromatography,” Am. Soc. Testing Materials Bull., No. 237, April, 1959, p. 74.Google Scholar