Phase equilibria in the Na,K,Mg,Ca‖SO4,Cl-H2O system at 50°C in the astrakhanite crystallization region

Phase equilibria of the Na,K,Mg,Ca‖SO₄,Cl-H₂O system at 50°C in the astrakhanite (Na₂SO₄ · MgSO₄ · 4H₂O) crystallization region were studied using the translation method. Astrakhanite was found to be involved, as an equilibrium phase of the title system, in 35 divariant fields, 39 monovariant curves, and 22 invariant points. The data gained were used to construct a fragment of a schematic equilibrium phase diagram of the title system in the astrakhanite crystallization region.     

Phase equilibria in the Na,K‖SO4,HCO3,F-H2O system at 0°C

Phase equilibria in the Na,K‖SO₄,HCO₃,F-H₂O system at 0°C are studied by the translation method. Fifteen divariant double-saturation fields, 13 monovariant triple-saturation curves, and five invariant quadruple-saturation points are distinguished in the system at 0°C. A global phase diagram (phase complex) of the title system at 0°C is designed.     

Phase equilibria in the Na,K,Mg,Ca‖SO4,Cl-H2O system at 50°C in the halite crystallization field

Phase equilibria of the Na,K,Mg,Ca‖SO₄,Cl-H₂O system at 50°C in the halite (NaCl) crystallization field were studied using the translation method. Halite, which is an equilibrium phase of the title system at 50°C, was found to be involved in 25 invariant points, 59 monovariant curves, and 43 divariant fields. A fragment of the equilibrium phase diagram of the title system in the halite crystallization field was constructed.     

Phase equilibria in the Na, K∥SO4, CO3, F-H2O system at 0°C

Phase equilibria in the Na, K‖SO₄, CO₃, F-H₂O system at 0°C are studied by the translation method. Eighteen divariant fields, 16 monovariant curves, and five invariant points are distinguished in the system. The first closed phase diagram (phase complex) of the title system is designed on the basis of these results. Original Russian Text ? Sh.Kh. Avloev, L. Soliev, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 6, pp. 1046–1051.     

Phase equilibria in the Na,Ca||SO4,CO3,F-H2O system at 25°C

Phase equilibria in the Na,Ca|SO₄,CO₃,F-H₂O system at 25°C have been studied using the translation method. The existence of seven invariant points, 21 monovariant curves, and 22 divariant fields has been established. These data were used to construct a looped phase diagram (phase complex) for the title system at 25°C.     

Phase equilibria in the Na,K∥SO4,CO3,HCO3-H2O system at 0°C

Phase equilibria in the Na,K∥SO₄,CO₃,HCO₃-H₂O system at 0°C are studied by the translation method. Twenty two divariant fields, 21 monovariant curves, and seven invariant points are distinguished in the system at 0°C. The first global phase diagram (phase complex) of the title system is constructed on the basis of these results.     

Phase equilibria in the Na,K‖CO3,HCO3,F-H2O system at 50°C

Phase equilibria in the Na,K??CO₃,HCO₃,F-H₂O system at 50°C have been determined using the translation method. The system is found to be characterized by the existence of 21 divariant double-saturation fields, 19 monovariant triple-saturation curves, and six invariant quadruple-saturation points. A looped phase diagram (phase complex) for the title system at 50°C has been constructed.     

Phase equilibria in the Na,K||CO3,HCO3,F-H2O system at 0°C

Phase equilibria in the Na,K||CO₃,HCO₃,F-H₂O system at 0°C are studied by the translation method. Seventeen divariant double-saturation fields, 16 monovariant triple-saturation curves, and five invariant quadruple-saturation points are distinguished in the system at 0°C. A global phase diagram (phase complex) of the title system at 0°C is designed.     

Phase equilibria of the Na,K,Mg,Ca//SO4,Cl-H2O system at 50°C in the crystallization range of glaserite 3K2SO4·Na2SO4

Phase equilibria of the Na,K,Mg,Na,K,Mg,Ca//SO₄,Cl-H₂O system are studied at 50°C via translation in the crystallization range of glaserite (3K₂SO₄ · Na₂SO₄). It is found that glaserite as the equilibrium phase of the investigated system at 50°C participates in the formation of 21 invariant points, 21 monovariant curves, and 34 divariant fields. A fragment of the phase equilibria diagram of the investigated system is constructed in the crystallization range of glaserite.     

Phase equilibria in the Na,Ca‖SO4,CO3,F-H2O at 0°C

Phase equilibria in the Na,Ca‖SO₄,CO₃,F-H₂O system at 0°C were studied using the translation method. Seven invariant points, 18 monovariant curves, and 17 divariant fields were found to exist. A looped phase diagram (phase complex) of the title system was constructed.     

Solubilities in the Na,Ca‖SO4,F-H2O system at 0°C

Solubilities at invariant points of the Na,Ca‖SO₄,F-H₂O system at 0°C was studied, and a phase diagram of this system at 0°C was constructed.     

Phase equilibria in the Na,K,Mg,Ca∥SO<Subscript>4</Subscript>,Cl–H<Subscript>2</Subscript>O system at 50°С in the polyhalite crystallization region

Phase equilibria of the Na,K,Mg,Ca||SO₄,Cl–H₂O system at 50°С in the polyhalite (K₂SO₄ · MgSO₄ · 2CaSO₄ · 2H₂O) crystallization region were studied using the translation method. Polyhalite was found to be involved, as an equilibrium phase of the title system at 50°С, in 17 invariant points, 36 monovariant curves, and 24 divariant fields. A fragment of equilibrium phase diagram of the title system in the polyhalite crystallization region was constructed.     

Phase complex of the Na,K‖Br,MoO4 system

The Na,K‖Br,MoO₄ system was studied by differential thermal analysis and X-ray powder diffraction. It was established that the liquidus surface consists of the crystallization fields of the initial components and the incongruently melting compound NaKMoO₄. The coordinates of three nonvariant points were determined, which represent one eutectic, E ^Δ, and two peritectics, P ₁ ^Δ , and P ₂ ^Δ , with the melting points 472, 512, and 538°C, respectively, and the specific enthalpies of melting Δ_melt H = 177, 230, and 184 kJ/kg, respectively.     

Phase equilibria in the stable tetrahedron NaF-KF-KBr-K2CrO4 of the quaternary mutual system Na,K‖F,Br,CrO4

The stable triangle NaF-KBr-K₂CrO₄ and the united stable tetrahedron NaF-KF-KBr-K₂CrO₄ of the quaternary mutual system Na,K‖F,Br,CrO₄ were studied by differential thermal analysis, and the characteristics of eutectics were determined.     

Phase equilibria in the Ag–Au–In system at 500°C

Phase equilibria in Ag–Au–In system at 500°C are investigated by means of electron microscopy, electron probe microanalysis, and X-ray powder diffraction. The part of the system’s isothermal cross section with an indium content of up to 50 at % is constructed.     

Solubility in the NaCl-ZrOCl2-HCl-H2O system at 25, 50, and 75°C

Solubilities were studied in the NaCl-ZrOCl₂-HCl-H₂O water-salt system along the 28 wt % HCl section at 25, 50, and 75°C. This is a eutonic system. The compositions of the eutonic solution are as follows (wt % NaCl, ZrOCl₂ · 8H₂O, HCl, and H₂O, respectively): at 25°C, 0.26, 1.88, 27.4, and 70.46; at 50°C, 2.82, 2.68, 26.46, and 68.04; and at 75°C, 1.9, 16.1, 22.96, and 59.04.     

Phase equilibria in the ternary reciprocal system Li,Rb‖F,CrO4

The ternary reciprocal system of fluorides and chromates of lithium and rubidium was studied for the first time. The stable pair of salts LiF and Rb₂CrO₄ and also binary compounds on the bordering sides partition the system into five simplexes. Studying a number of polythermal sections allowed us to determine the melting points and compositions of two peritectics and three eutectics. The crystallization fields of phases in the system were demarcated, and phase equilibria were described.     

Phase equilibria in the ErPO4–K3PO4 system

The phase equilibria occurring in the ErPO₄–K₃PO₄ system were investigated by the thermal analysis, FTIR, and X-ray powder diffraction methods. On the basis of obtained results, the related phase diagram is proposed. This system includes one intermediate compound, K₃Er(PO₄)₂; the double phosphate melts incongruently at 1355 °C and occurs in two polymorphic forms; transformation β/α-K₃Er(PO₄)₂ proceeds at 420 °C. The eutectic occurs at the composition of 58.5 wt% K₃PO₄, 41.5 wt% ErPO₄ at 1317 °C.     

Cobalt tungstate synthesis in melts of the (K2WO4-KCl)eut-CoSO4 (K,Co‖Cl,SO4,WO4) system

A rational process is developed for preparing cobalt tungstate. Cobalt tungstate samples are synthesized and identified in melts of the(K₂WO₄-KCl)_eut-CoSO₄ (K,Co‖Cl,SO₄,WO₄) system.