Impurity gradients in solution-grown ice and MgSO4 center dot 12H(2)O crystals measuredby cryo-laser ablation and high-resolution-induced-coupled plasma mass spectrograph


Gartner R. S. , GENCELI F. E. , TRAMBITAS D. O. , WITKAMP G. J.

JOURNAL OF CRYSTAL GROWTH, cilt.275, 2005 (SCI İndekslerine Giren Dergi) identifier identifier

Özet

During the eutectic freeze crystallization (EFC) of an industrial aqueous MgSO4 solution, ice and magnesium sulfate duodecahydrate (MgSO4 center dot 12H(2)O(s)) were crystallized simultaneously near the eutectic point. It was found that the crystallization was highly selective: although the industrial feed solution contained appreciable levels of inorganic impurities (typically: 320 mg/LCl, 410 mg/LCa2; 40 mg/LMn2+; 70 mg/L Na+ and 50 mg/LK+), the formed ice and salt crystals contained lower levels of impurities (typically: 17 mg/LCl-; 8 mg/LCa2+; 17 mg/LMn2+; and 5 mg/LNa). Also the ice was pure: only traces (typically: 20 mg/LSO42- and 5 mg/LMg2+) of magnesium and sulfate were found in the ice crystals.