The translation method of determining phase equilibria and construction of phase diagrams for multicomponent systems was applied to investigate the phase equilibria in two quaternary Na, NH 4 //SO 4 , Cl−H 2 O (at 100°C , 10°C) and Na 2 SO 4 −K 2 SO 4 −MgSO 4 −H 2 O (at 35°C) and three quinary Li, K//Cl, CO 3 , B 4 O 7 −H 2 O (at 0°C), Na, K//Cl, SO 4 , B 4 O 7 −H 2 O (at 50°C), and Na, K//Cl, CO 3 , B 4 O 7 − H 2 O (at 25°C) water−salt systems. The comprehensive closed phase equilibria diagrams for each of the systems were constructed at the relevant temperatures.The constructed diagrams for the quinary systems were fragmented into trivariant crystallization volumes for each of the available individual solid phases in the systems. The available experimental results on each of the three investigated quinary systems compose only a portion of the phase equilibria data obtained by us using the techniques of translation method. Comparison of our results with the available literature data for the two quinary Li, K//Cl, CO 3 , B 4 O 7 −H 2 O (at 0°C) and Na, K//Cl, SO 4 , B 4 O 7 − H 2 O (at 50°C) systems shows agreement.

Phase equilibria in quinary Na, K//Cl, SO4, B4O7–H2O system at 25 °C were investigated by means of translation method. Five invariant points, 16 monovaraint curves, and 18 divariant fields have been determined in the system on quinary composition. A comprehensive phase equilibria diagram for the system was constructed on the basis of obtained data. The diagram was fragmented into divariant cocrystallization fields and trivariant volumes of two different solid phases and individual equilibrium solid phases, respectively. The comparison of obtained results with available experimental data was deliberated.

at 15 °C were investigated by means of translation method. The quinary invariant points, monovariant curves, divariant fields, and trivariant volumes which are saturated with four, three, two, and one solid phases with relevant equilibrium liquid phases, respectively, were determined in each of the systems. Two points, seven curves, and nine fields were determined in the Li, Na, K, Sr//Cl−H 2 O system at 25 °C. Six points, 18 curves, and 19 fields were found in the Li, Na, K//SO 4 , B 4 O 7 −H 2 O system at 0 °C. Seven points, 20 one curves, and 20 two fields were determined in the Na, K, Mg//SO 4 , B 4 O 7 −H 2 O system at 15 °C on the quinary level. The total phase equilibria diagrams of each of the systems were constructed. The constructed diagrams were fragmented into trivariant crystallization volumes of equilibrium solid phases. The obtained volumes reflected the structures of projected diagrams of systems saturated with relevant equilibrium solid phases and involved the recent experimental results on KCl, Li 2 B 4 O 7 along with Na 2 B 4 O 7 , and MgB 4 O 7 •9H 2 O saturated parts of the quinary systems: Li, Na, K, Sr//Cl−H 2 O at 25 °C, Li, Na, K//SO 4 , B 4 O 7 − H 2 O at 0 °C, and Na, K, Mg//SO 4 , B 4 O 7 −H 2 O at 15 °C, respectively. The obtained results clarified the reciprocal relations of phase conglomerates in the systems comprehensively.

The translation method which can produce all the geometrical figures and closed phase equilibria diagram for multicomponent water-salt systems was described. The phase equilibria in quinaryNaCl - KCl -MgCl2 - CaCl2 - H2O (25°C) system which is an important part of the more complex oceanic Na, K, Mg, Ca//Cl, SO4- H2O system were determined using translation method. Three invariant points of quadruple saturation, tenmonovariant curves of triple saturation and twelvedivariant fields of double saturation salts were identified in the system. Two of the curves extend between the quinary invariant points while the other eightare generated from extension of the relevant quaternary invariant points into the quinary composition. A total phase equilibria diagram for the quinary NaCl - KCl - MgCl2 - CaCl2 - H2O system at 25°C was constructed on the basis of obtained results. The diagram was fragmented into divariant fields of common crystallization of two salts. A good agreement was observed between the results obtained in this work and the available data in literature.

Isothermal methods of investigation of quinary systems and advantages of use of the translation method for investigation of quinary water−salt systems were discussed. Two quinary systemsLi, Na, K//CO 3 , B 4 O 7 −H 2 O and Na, K//Br, SO 4 , B 4 O 7 −H 2 Owere investigated by means of the translation method at 15 and 25 °C, respectively. The comparison showed a good agreement between our results and the available literature data. There are 4 points, 13 curves, and 15 fields saturated with 4, 3, and 2 different equilibrium solid phases, respectively, in Li, Na, K//CO 3 , B 4 O 7 −H 2 O systems at 15 °C. The quinary Na, K//Br, SO 4 , B 4 O 7 −H 2 O system at 25 °C involves 5 invariant points, 16 monovariant curves, and 18 divariant fields saturated with 4, 3, and 2 different equilibrium solid phases, respectively. The total phase equilibria diagrams of both of the quinary systems were constructed on the basis of obtained data. The obtained diagrams were fragmented into divariant cocrystallization fields saturated with two different equilibrium solid phases. The trivariant crystallization volumes, which reflect the structures of Janecke dry-salt phase diagrams of the systems saturated with the relevant phases, were also extracted.