Izvestiya of Saratov University.
ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)


visual-polythermal method

Phase Equilibria and Critical Phenomena for Cut 3 of the Qua­ ternary System Water - Pyridine - Butyric Acid - Potassium Chloride

Phase equilibria and critical phenomena in cut 3 of the quaternary system water - pyridine - butyric acid - potassium chloride whose constituent ternary liquid system had a closed binodal curve were studied by means of the visual-polythermal method within 5-90°C. We have determined the temperature dependence of the solution composition corresponding to the critical solution point of the immis- cibility region.

Topological Transformation of the Phase Diagram of the Ternary System Potassium Formate - Water - n.Butoxyethanol

Phase equilibria and critical phenomena in the ternary system potas­ sium formate - water - n.butoxyethanol, where a constituent binary liquid system is characterized by phase separation with a closed delamination region, were studied by means of the visual-polythermal method within 25-170°C. The temperature dependences of the com­ positions of the mixtures corresponding to the critical solubility points in the delamination region were determined.

Topological Transformation of Phase Diagrams for Сut 1 of the Quaternary System Potassium Nitrate – Water – Pyridine – Butyric Аcid in 5–60оС

Phase equilibria and critical phenomena in component mixtures of the cut 1 of the quaternary system Potassium Nitrate – Water – Pyridine – Butyric Аcid whose constituent ternary liquid system had a closed binodal curve were studied by means of the visualpolythermal method within 5–60oC. The volumes of two monotectic states in the composition tetrahedron have been found to be in contact via critical tie lines with increasing temperature.

Topological Transformation of Phase Diagram for Сut 2 of the Composition Tetrahedron of the Quaternary Potassium Nitrate – Water – Pyridine – Butyric Аcid System within 5–60°С

Phase equilibria and critical phenomena in component mixtures of the cut 2 of the composition tetrahedrone of the quaternary system potassium nitrate + water + pyridine + butyric acid whose constituent ternary liquid system had a closed binodal curve were studied by means of the visual-polythermal method within 5– 60°C. We first proposed a method to find the coordinates of the end point of the critical tie line of monotectic state in quaternary systems salt + three solvents.