Solubility and Phase Diagram for the Quaternary System Na2CO3 + Na2SO4 + H2O2 + H2O at 293 K

Solubility data for the Na 2 CO 3 + Na 2 SO 4 + H 2 O 2 + H 2 O system at 293 K were determined by Schreinmaker's method. The results were used to construct a phase diagram in the oblique projection according to the Janeck method. At constant temperature, when the hydrogen peroxide concentration is below 50 % (mass fraction), this diagram includes three invariant points, six double saturated liquid curves, and four crystallization fields corresponding to Na 2 CO 3 ·10H 2 O, Na 2 SO 4 ·10H 2 O, Na 2 CO 3 ·1.5H 2 O 2 ·H 2 O, and Na 2 SO 4 ·0.5H 2 O 2 ·H 2 O.