抄録
Mixed salt is obtained in bittern factories during the process of evaporating sea-salt bittern at the boiling temperatures up to about 124°C, and it is used as a component of fertilizer and others, For such uses, the product should be aged for 15-40 days to be completely solidified.
The authors studied the mechanism of solidification for the purpose of finding out the way as to how to rationalize the process. This paper reports the results of studies which were conducted to investigate the crystalline composition by means of X-Ray diffraction by using several specimens produced after various aging times in Utatsu Kagaku Factory in Kagawa Prefecture and several specimens prepared in our laboratory by boiling synthetic bitterns.
As the result, all of the mixed salt specimens were found to mainly consist of the mixture of crystals of sodium chloride and langbeinite, some carnallite, and various hydrates of magnesium sulphate.
From these results, the authors concluded as follows:
(1) The crystalline composition of the mixed salt is mainly the mixture of crystals of sodium chloride and langbeinite.
(2) Although the composition of the mixed salt is usually indicated by the percentages of NaCl, KCl, MgSO4, MgCl2 and H2O, it is considered preferable to indicate it by the percentages of NaCl, K2SO4, MgSO4, MgCl2 and H2O, or more correctly by the percentages of NaCl, K2SO4·2MgSO4, MgSO4, MgCl2 and H2O.