Izvestiya of Saratov University.

Chemistry. Biology. Ecology

ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)

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544.344.2 :544.344.012-16-14

Phase Equilibria and Critical Phenomena in the Water–i-Butyric Acid Binary System

Smotrov Maksim Pavlovich, Saratov State University

Phase equilibria and critical phenomena in the water-i-butyric acid binary system were studied by the visual polythermal method over the temperature range –10–30°C. The system is characterized by delamination with an upper critical solution temperature (UCST) equal 25.8°C. In the system at –1.8°C, these occurs a nonvariant monotectic equilibrium whose solid phase are ice crystals. The phase diagram of the system is plotted.


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