Size methods slurry quality

Common names have been given to sodium sulfate as a result of manufacturing methods. In rayon production, by-product sodium sulfate is separated from a slurry by filtration where a 7—10-cm cake forms over the filter media. Thus rayon cake was the term coined for this cake. Similarly, salt cake, chrome cake, phenol cake, and other sodium sulfate cakes were named. Historically, sulfate cakes were low purity, but demand for higher purity and controlled particle size has forced manufacturers either to produce higher quality or go out of business. Sodium sulfate is mined commercially from three types of mineral evaporites thenardite, mirabilite, and high sulfate brine deposits (see Chemicals frombrine). 

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