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The kinetics of hydration of calcium sulphate hemihydrate: A critical comparison of the models in the literature

✍ Scribed by R.J. Hand

Publisher
Elsevier Science
Year
1994
Tongue
English
Weight
511 KB
Volume
24
Category
Article
ISSN
0008-8846

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✦ Synopsis

The hydration of calcium sulphate hemihydrate to produce calcium sulphate dihydrate (gypsum plaster) has been the subject of several kinetic models, two of the most notable of which were proposed in a series of conflicting papers by Ridge and Schiller. Evidence was put forward in support of both these and other models but no model has gained universal support. Numerical calculations are used to compare these models with each other and with the Avrami kinetic equation in this paper. It is shown that at least for some ranges of data all three approaches are compatible and that within the limits of the experimental evidence presented so far there is no conclusive evidence which justifies the use of one model rather than the others.

πŸ“œ SIMILAR VOLUMES

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## Abstract Ammonium chloride solution is a satisfactory solvent for the calcium sulphate, anhydrite, and also very probably for gypsum. Extraction can be carried out completely on a β€”200 mesh material in a fairly short period. By means of this solution a differentiation can be made between the sul