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Smotrov M. P. Phase Equilibria and Critical Phenomena in the Water–i-Butyric Acid Binary System. Izvestiya of Saratov University. Chemistry. Biology. Ecology, 2016, vol. 16, iss. 1, pp. 21-24. DOI:

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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


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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