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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

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