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. Sodium chloride was found to delaminate mixtures of water and butyric acid in a wide concentration range. The compositions of the solutions corresponding to the critical solubility points at several temperatures were determined. The isothermal phase diagrams of the ternary system at 10.0, 25.0, 40.0, and 60.0° C were plotted, and the distribution coefficients of butyric acid between the liquid phases of monotectic state were calculated. The salting-out effect of butyric acid from its aqueous solutions by sodium chloride was shown to decrease with increasing temperature. The concentration of butyric acid in the organic phase of monotectics at 20.0° C is 92 wt.% with a distribution coefficient of 61.3. Sodium chloride was established to be an effective salting-out agent of butyric acid from its aqueous solutions in the range of 10.0?30.0° C and can be recommended for practical use.
1. Knunyants I. L., ed. Khimicheskaya entsiklopediya: v 5 t. [Chemical Encyclopedy: in 5 vols.]. Moscow, Sov. Entsiklopediya Publ., 1988–1998, vols. 1–5 (in Russian).
2. Ajay Kumar Jha, Jianzheng Li, Yixing Yuan, Nawraj Baral, Binling Ai. A Review on Bio-butyric Acid Production and its Optimization // Int. J. Agric. Biol. 2014. Vol. 16, № 5. P. 1019–1024. DOI: https://doi.org/13-1259/2014/16-5-1019-1024
3. Dwidar M., Park J.-Y., Mitchell R. J., Sang B.-I. The Future of Butyric Acid in Industry // The Scientifi c World J. 2012. Vol. 2012. P. 1–10. DOI: https://doi.org/10.1100/2012/471417
4. Fu H., Wang X., Sun Y., Yan L., Shen, J., Wang J., Yang S.-T., Xiu Z. Effects of salting-out and salting-out extraction on the separation of butyric acid // Separation and Purifi cation Technol. 2017. Vol. 180. P. 44–50. DOI: https://doi.org/10.1016/j.seppur.2017.02.042
5. Dan W., Hao C., Ling J., Jin C., Zhinan X., Peilin C. Effi cient Separation of Butyric Acid by an Aqueous Twophase System with Calcium Chloride // Chin. J. Chem. Eng. 2010. Vol. 18, № 4. Р. 533–537. DOI: https://doi.org/10.1016/S1004-95411060255-8
6. Ling Yan, Ya-Qin Sun, Xu-Dong Wang, Hong-Xin Fu, Ying Mu, Zhi-Long Xiu. Partition behavior of monocarboxylic acids in salting-out extraction systems of monohydric alcohols and dipotassium phosphate // Separation and Purifi cation Technol. 2018. Vol. 199. P. 351–358. DOI: https://doi.org/10.1016/j.seppur.2018.02.006
7. Krupatkin I. L., Rozhentsova E. P. About salting out secretly stratifi ed systems. University News. Chemistry and Chem. Technology, 1971, vol. 14, no. 8, pp. 1196–1199 (in Russian).
8. Cherkasov D. G., Il’In K. K. Salting out of butyric acid from aqueous solutions with potassium chloride. Russ. J. of Applied Chem., 2009, vol. 82, no. 5, pp. 920–924 (in Russian). DOI: https://doi.org/10.1134/S1070427209050346
9. Cherkasov D.G., Chepurina Z.V., IlIn K.K. Phase equilibria and critical phenomena in the cesium nitrate-waterbutyric acid ternary system at 5–100° C. Russ. J. Phys. Chem. A, 2015, vol. 89, no. 8, pp. 1396–1401 (in Russian). DOI: https://doi.org/10.1134/S0036024415080063
10. Treibal R. Zhidkostnaya ekstraktsiya [Liquid Extraction]. Moscow, Khimiya Publ., 1966. 724 p. (in Russian).
11. Cherkasov D. G., Kurskii V. F., IlIn K. K. Topological transformation of the phase diagram for the ternary system cesium nitrate-water-acetonitrile. Russ. J. of Inorg. Chem. 2008, vol. 53, no. 1, pp. 139–145 (in Russian). DOI: https://doi.org/10.1134/S0036023608010208
12. Kuznetsova I. K., Bergman A. G. Thermal analysis of the urea-water-butyric acid ternary system. Russ. J. Gen. Chem., 1956, vol. 26, no. 5, pp. 1335–1340.
13. Krupatkin I. L., Rozhentsova E. P. On the behavior of double covertly stratifi ed systems in ternary systems. Russ. J. Phys. Chem., 1970, vol. 44, no. 4, pp. 1036–1039 (in Russian).
14. Kafarov V. V., ed. Spravochnik po rastvorimosti. Binarnye sistemy [Manual in Solubility: Binary Systems]. Moscow, Leningrad, Akad. Nauk SSSR, 1963, vol. 1, books 1, 2. 1960 p. (in Russian).
15. Kirgintsev A. N., Trushnikova L. N., Lavrent’eva V. G. Rastvorimost’ neorganicheskikh veschestv v vode [Solubility of Inorganic Substances in Water]. Leningrad, Khimiya Publ., 1972. 248 p. (in Russian).