Reaction between NaCI and K₂SO₄ Powders Due to Adsorbed Water

Abstract

Watervaor ad80rption on NaCI and KaSOs P wder mixtures which were prepared under a vacuum of 10 6 Hg, has been investigated, Am unts r adsq s rfqre areas and X-ray diffr ction pattems were de erm ed the samples u der variOUs water vapor pressures.
The surface area and the capacity fawater adsorptl non the samPle be t I crease by presorbing water at relative vapor pressure above 0.34. The X-ray diffraction data of the mixture indicated that NaCI reacted with K2SO4 in the presence of adsorbed water as follws
NaCI K12SO4 KCI (Na, k)2SO2
The above stated increase of the surface area was interpreted to be caused by the microcrysstal de: position of rea6tion pro cts. The coverages of Water adsorbed on both s 1ts a the relat ve pressure of O.34 were estimated to be 2 Oon NaCr and 1 30 K3SO from the-water adsorption isetherms It 8 con3idered that these values cor respond to the e st thick ess of above solid reacti n n the salt 3urface,