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Quantitative X-Ray Diffraction Analysis of Calcium Sulfates and Quartz in Wet-Process Phosphoric Acid Filter Cakes

Published online by Cambridge University Press:  06 March 2019

Kjell R. Waerstad
Kjell R. Waerstad*
Affiliation:
Tennessee Valley Authority, Muscle Shoals, Alabama. 35660
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Abstract

A quantitative X-ray diffraction method has been developed for rapid determination of the crystalline phases present in by-product filter cakes from wet-process phosphoric acid manufacture. A new technique to reduce preferred orientation of the crystallites by removing the top layer of the X-ray samples with adhesive tape is described, statistical analysis of synthetic sample mixtures of CaS04.2H2O, CaSO4 · 0.5H20, CaSo4, and α-Si02 indicates that the calcium sulfate phases present in typical filter cakes can be determined with an accuracy of about 3% at the 95% confidence level; quartz can be determined at about 14%. The method has been applied to the analysis of 10 filter-cake samples from an experimental hemihydrate plant. The results are in good agreement with data from X-ray fluorescence and chemical analyses

Type
Research Article
Information
Advances in X-Ray Analysis , Volume 29: Thirty-Fourth Annual Conference on Applications of X-ray Analysis, August 5-9, 1985 , 1985 , pp. 211 - 216
Copyright
Copyright © International Centre for Diffraction Data 1985

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References

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