Suchergebnisse

Method of obtaining potassium sulfate with basic substance content higher 92 % shown. Process conditions: 110 % KCl (10 % excess substance from stoichiometry), mixing at temperature higher 95 °C during 30 min, mixing at temperature 0 °C for 1 hour, stirrer speed 500 rpm, sludge washing 15 % water from wet sludge weight, drying the washed sludge at 70–80 °C during 1 hour. The degree of evaporation of the solution at which the double salt of potassium and ammonium sulfate precipitated was determined. The degree is 30 % at the evaporated suspension cooled, and is 45 % at hot filtration.

This work shows the possibility of obtaining potassium sulfate by converting phosphogypsum and potassium carbotane by the reaction CaSO4 + K2CO3 → ↓ CaCO3 + K2SO4. The optimal conditions for this process are determined. It is shown that in an aqueous medium at a temperature of 20 °C, a stoichiometric ratio of the initial components, the rotation speed of the stirrer 200 rpm for 15-30 min, the degree of use of Ca2+ ions is 94-95 %. Potassium sulfate contained in the liquid phase is transferred into the solid phase by evaporation and subsequent crystallization.

The possibility of purification of circulating solutions containing triethanolamine from CaCl2 impurities by introducing into them potassium carbonate is shown. This process procceds according to the reaction K2CO3 + CaCl2 → ↓CaCO3 + 2KCl. The influence of the consumption rate of potassium carbonate has been studied. It is shown that at the stoichiometric consumption rate of K2CO3, the content of Ca2+ ions in the liquid phase was 0,02 %, while with a K2CO3 deficiency of the stoichiometric consumption rate of 70 and 50 %, this value was 0,43 and 0,92 %, respectively. It has been established that the circulating solutions purified from CaCl2 can be used in the conversion of new portions of KCl and phosphogypsum.