Modern Physicochemical Equilibrium Description in Na2O–Al2O3–H2O System and Its Analogues
- 1 — Saint-Petersburg Mining University
- 2 — Saint-Petersburg Mining University
- 3 — Saint-Petersburg Mining University
- 4 — Saint-Petersburg Mining University
Abstract
Equilibrium and non-equilibrium states of systems Na 2 O–Al 2 O 3 –H 2 O and K 2 O–Al 2 O 3 –H 2 O are crucial for establishing key technological parameters in alumina production and their optimization. Due to a noticeable discrepancy between experimental results and thermodynamic calculations based on materials of individual researchers the necessity of systematization and statistical processing of equilibrium data in these systems to create a reliable base of their physicochemical state, analysis and mathematical modeling of phase equilibria is substantiated. The tendency to a decrease of the hydration degree of solid sodium aluminates with increasing temperature and the transition of systems from the steady state of gibbsite to equilibrium with boehmite is revealed. The paper contains approximating functions that provide high-precision description of equilibrium isotherms in technologically significant area of Na 2 O–Al 2 O 3 –H 2 O and K 2 O–Al 2 O 3 –H 2 O concentrations. Approximating function can be simplified by dividing the isotherm into two sections with the intervals of alkaline content 0-0.25 and 0.25-0.4 mole/100 g of solution. The differences in solubility isotherms for Na 2 O–Al 2 O 3 –H 2 O and K 2 O–Al 2 O 3 –H 2 O systems provide are associated with changes in the ionic composition solutions that depends on concentration and temperature, as well as differences connecting with alkali cation hydration, which is crucially important for thermodynamic modeling of equilibria under consideration.
References
- Arlyuk B.I., Veprikova T.B. Dependency of Hydrargyllite Solubility on Concentration of Sodium Alkali and Temperature. Tsvetnye metally. 1981. N 6, p. 59-60 (in Russian).
- Druzhinina N.K. Diaspore Solubility in Aluminate Solutions. Tsvetnye metally. 1955. N 1, p. 54-56 (in Russian).
- Kuznetsov S.I., Derevyankin V.A. Physical Chemistry of Alumina Production Using Bayer Method. Мoscow: Metallurgizdat. 1964, p. 353 (in Russian).
- Lainer Yu.A., Kitler I.N. Metallurgy of Non-Ferrous and Rare Metals. Мoscow: Nauka. 1967, p. 194-199 (in Russian).
- Lyapunov A.N., Khodakova A.G., Galkina Zh.G. Hydrargyllite Solubility in Alkali Solutions of Sodium Hydroxide, Containing Soda and Sodium Chloride, under 60 and 95 °С. Tsvetnye metally. 1964. Vol. 37, p. 48-51 (in Russian).
- Magarshak G.K. Polytherms in the System Al2O3–Na2O–H2O under 30-200 °С. Legkie metally. 1938. Vol. 7. N 2,
- p. 12-16 (in Russian).
- Mazel' V.A. Alumina Production. Мoscow: Metallurgizdat. 1955, p. 430 (in Russian).
- Lainer A.I., Eremin N.I., Lainer Yu.A., Pevzner I.Z. Alumina Production. Мoscow: Metallurgiya. 1978, p. 344 (in Russian).
- Sizyakov V.M., Korneev V.I., Andreev V.V. Increasing the Quality of Alumina and Co-Products During Nepheline Processing. Мoscow: Metallurgiya. 1986, p. 118 (in Russian).
- Sizyakov V.M. Chemical and Engineering Patterns of Sintering Processes in Alkali Alumosilicates and Hydrochemical Processing of Sintered Material. Zapiski Gornogo instituta. 2016. Vol. 217, p. 102-112 (in Russian).
- Metallurgist’s Guidelines on Non-Ferrous Metals. Alumina Production. Ed. by Yu.V.Baimakova, Ya.E.Kantorovich. Мoscow: Metallurgiya, 1970, p. 320 (in Russian).
- Abramov V.Ya., Stel'makova G.D., Nikolaev I.V. et al. Physico-Chemical Outlines of Complex Processing of Aluminum Raw Materials (Alkali Methods). Мoscow: Metallurgiya, 1985, p. 288 (in Russian).
- Chizhikov D.M., Kitler I.N., Lainer Yu.A. Chemistry and Alumina Technology. NTISNKh Arm. SSR. Erevan, 1964, p. 233-342 (in Russian).
- Tsyrlina S.M. Solubility of Aluminum Hydroxide in Caustic Soda Solutions (System Al(OH)3–NaOH–H2O). Legkie metally. 1936. № 7, p. 28-37 (in Russian).
- Chen N.Y. Physical Chemistry of Alumina Production. Shanghai: Scientific and Technical Publishers. 1962, p. 325.
- Du C., Zheng S., Zhang Y. Phase equilibria in the K2O–Al2O3–H2O system at 40 C. Fluid Phase Equilibria. 2005. Vol. 238, p. 239-241.
- Fricke R., Jucaitis P. Untersuchungen über die Gleichgewichte in den Systemen Al2O3–Na2O–H2O und Al2O3–K2O–H2O. Zeitschrift für anorganische und allgemeine Chemie. 1930. Band 191, p. 129-149.
- Ikkatai T., Okada N. Viscosity, specific gravity and equilibrium concentration of sodium aluminate solutions. Extractive Metallurgy of Aluminum. 1963. Vol. 1, p. 159-173.
- Israelachvili J.N. Intermolecular and Surface Forces. London: Academic Press. 2011, p. 706.
- Pál Sipos. The structure of Al(III) in strongly alkaline aluminate solutions A review. Journal of Molecular Liquids. 2009. Vol. 146. Iss. 1, 2, p. 1-14.
- Ma S., Zheng S., Zhang Y., Zhang Yi. Phase Diagram for the Na2O−Al2O3−H2O System at 130 °C. Journal of Chemical and Engineering Data. 2007. Vol. 52. Iss. 1, p. 77-79.
- Wei J., Zheng S., Du H., Xu H., Wang S., Zhang Yi. Phase Diagrams for the Ternary Na2O−Al2O3−H2O System at 150 and 180 °C. Journal of Chemical and Engineering Data. 2010. Vol. 55. Iss. 7, р. 2470-2473.
- Qiu G., Chen N. Phase study of the system Na2O-Al2O3-H2O. Canadian Metallurgical Quarterly. 1997. Vol. 36. Iss. 2, p. 111-114.
- Russell A.S., Edwards J.D., Taylor C.S. A solubility and Density of Hydrate Alumina in Sodium solutions. Journal of Metals. 1955. Vol. 7, p. 1123-1128.
- Sprauer J.W., Pearce D.W. Equilibria in the Systems Na2O–SiO2–H2O and Na2O–Al2O3–H2O at 25 °C. Journal of Physical Chemistry. 1940. Vol. 44. Iss. 7, p. 909-911.
- Zhang Y., Li Y., Zhang Yi. Phase Diagram for the System Na2O−Al2O3−H2O at High Alkali Concentration. Journal of Chemical and Engineering Data. 2003. Vol. 48. Iss. 3, p. 617-620.