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


масляная кислота

Phase behavior and solubility of components of the binary butyric acid – polyethylene glycol-1500 system

A critical review of the literature on the methods of concentration and extraction of biobutyric acid from fermentation solutions has been carried out. The best results of these processes are achieved by combining extraction with salting. It is proposed to use polyethylene glycols with diff erent molecular weights as non-fl ammable and environmentally friendly extractants.

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.

ВСАЛИВАНИЕ – ВЫСАЛИВАНИЕ В ЧЕТВЕРНОЙ СИСТЕМЕ ВОДА – ПИРИДИН – МАСЛЯНАЯ КИСЛОТА – ИОДИД КАЛИЯ. РАЗРЕЗ 1

Визуально-политермическим методом в интервале 5–60°С исследованы фазовые равно-
весия и критические явления в разрезе 1 тетраэдра состава четверной системы вода–
пиридин–масляная кислота–иодид калия, включающей тройную жидкостную систему с
замкнутой областью расслаивания. Найдены зависимости состава критических точек рас-
творимости от температуры. Изотермы фазовых состояний системы, построенные на пло-
скости треугольника разреза при восьми температурах, позволили выявить топологическую

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.

Equilibrium Liquid–Liquid–Solid and Critical Phenomena in the Quaternary System Cesium Nitrate+Water+Pyridine+Butyric Acid with in the Range of 5 to 60°C

Phase equilibria and critical phenomena in the component mixtures of a cut of the composition tetrahedron of the quaternary system cesium nitrate + water + pyridine + butyric acid were studied in the range of 5–60°C by the visual-polythermic method. The phase equilibria in the component mixtures were studied using sections of one cut of the composition tetrahedron.

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.

Phase Equilibria and Salting Out of Butyric Acid in the Sodium Chloride – Water – Butyric Acid Ternary System

Phase equilibria in the water–butyric acid binary system in the range of ?10?0° C and in the sodium chloride–water–butyric acid ternary system in the range of 10.0?60.0° C were studied using the visual polythermal method. The phase diagram of the water–butyric acid binary system at ?9.5° C is characterized by eutectic equilibrium, the solid phases of which being ice and butyric acid crystals. The metastable delamination range was found on the ice crystallization field, bounded by a binodal curve with an upper critical solution temperature of ?3.7° C.