Gipslöslichkeiten in wässerigen Systemen mit NaCl,MgCl2, Na2SO4 und MgSO4

Gypsum solubilities in aqueous systems containing NaCl, MgCl₂, Na₂SO₄, and MgSO₄ Solubilities of Gypsum (CaSO₄·2H₂O) have been determined within the systems MgSO₄–MgCl₂–NaCl–H₂O and MgSO₄–Na₂SO₄–NaCl–H₂O at 21 different compositions of solutions per concentration range (0.01, 0.05, 0.1, 0.15, 0.5, and 1.0mol/l) of total easily soluble salt. Lines of equal solubilities of gypsum can be constructed form these data. They make possible to estimate gypsum solubility in solutions of similar composition. Small quantities of KCl or KNO₃ may be taken as NaCl. Solubilities measured under percolation conditions deviate sometimes to lower, those measured at supersaturation to higher values. The tendency to supersaturation lowers with increasing content of crystal-solution interfaces within the system. At concentrations of easily soluble salts from 0,01 to 0,15mol/l the solubility of gypsum is governed by the CL^?:SO⁼ ₄-ratio. Concentration of solution or Na⁺:Mg⁺⁺ -ratio are of lower efficiency.