Abstract
In separating NS salt B from various bitterns at 100°C and 50°C, calculations and studies on the yield of potassium, quantity of magnesium hydroxide to be added, quantity of water to be evaporated etc. were done using the phase diagrams of the quinary system KCl-K2SO4-MgCl2-MgSO4-Mg(OH) 2-H2O. The yield of potassium as NS salt B from bittern was calculated to be about 50 per cent at 100°C and about 80 per cent at 50°C.
Phase diagram indicating the interrelation between the kind of deposited triple salt and the sodium content of original bittern was also completed.
Tests for the separation of NS salt B with 1 ton open pan were made at Onahama Salt Plant of the Japan Monopoly Corporation, and by the results of these tests, it was found to be possible to separate potassium in bittern directly in the form of sulfate. Furthermore, it was confirmed that boron dissolved in bittern was partly codeposited in NS salt B, which was found to contain about 0.6-0.7mg-B per gram solid of triple salt.
