Features of the synthesis of highly dispersed alumophosphates AlPO4·nH2O
https://doi.org/10.29235/1561-8331-2021-57-3-310-319
Abstract
Aluminum orthophosphate of the composition AlPO4·2H2O with a monoclinic structure identical to the structure of the natural mineral metavariscite was obtained by condensation method during hydrothermal treatment of alumophosphate solutions with a concentration (g/l) of Al2O3 90 – 115, P2O5 340 – 440 in the temperature range 95–99 °C. For the first time, the role of aging of the alumophosphate system in shortening of the induction period, simultaneous nucleation of primary particles in the entire volume of the solution and the formation of a pasty product with a predominant particle size of 1–10 μm, in contrast to 30–50 μm, characteristic of a fine-crystalline product obtained without aging of the solution, is established. It is shown that pasty AlPO4·2H2O, in comparison with fine-crystalline, is hardly soluble in HCl even under prolonged heating. The influence of P2O5 content in the alumophosphate solution, the conditions of its aging and the duration of hydrothermal treatment on the particle size distribution for synthesized aluminum orthophosphates have been established. Anhydrous alumophosphate obtained by dehydration of pasty AlPO4·2H2O in the temperature range of 150–200 °C with subsequent heat treatment at 900 °C is readily soluble in acids, and the predominant particle size is 5–13 μm.
About the Authors
L. S. Eshchenko
Belarusian State Technological University
Belarus
Belarus
Lyudmila S. Eshchenko – D. Sc. (Engineering), Professor
13a, Sverdlova Str., 220006, Minsk
A. V. Paniatouski
Belarusian State Technological University
Belarus
Belarus
Aleh V. Paniatouski – M. Sc.
13a, Sverdlova Str., 220006, Minsk
References
1. Greben’ko N. V., Eshchenko L. S., Kushel’ M. I. Influence of conditions for obtaining aluminum phosphates on their physicochemical properties. Izvestiya VUZov. Khimiya I khimicheskaya tekhnologiya = Russian journal of chemistry and chemical technology, 1976, vol. 19, iss. 7, pp. 1070–1073 (in Russian).
2. Greben’ko N. V., Eshchenko L. S., Pechkovskii V. V. Preparation and properties of aluminum orthophosphates. Izvestiya Akademii nauk SSSR. Neorganicheskie materialy = Proceedings of the NAS of the USSR. Inorganic materials, 1978, vol. 14, iss. 3, pp. 136–140 (in Russian).
3. Eshchenko L. S., Laevskaya E. V., Korobko E. V., Novikova Z. A. Preparation of fillers for ERS based on hydrated aluminum orthophosphate. Trudy BSTU, Seriya Khimiya i tekhnologiya neorganicheskikh veshchestv = Proceedings of BSTU. Chemistry and technology of inorganic substances, 2015, no. 3, pp. 56–63 (in Russian).
4. Laevskaya E. V., Eshchenko L. S., Korobko E. V., Novikova Z. A., Unal Kh. I. Influence of the structure of aluminum orthophosphate dihydrate on its electrorheological activity. Teplo- i massoperenos-2014: sbornik nauchnykh trudov [Heat and mass transfer – 2014: collection of articles]. Minsk, A. V. Luikov Institute of Heat and Mass Transfer of the National Academy of Sciences of Belarus, 2015, pp. 263–270 (in Russian).
5. Eshchenko L. S., Ponyatovskii O. V., Korobko E. V., Novikova Z. A. Development of compositions of dispersed fillers for ERS. Materialy XI Mezhdunarodnoi nauchnoi konferentsii «Fullerenyi nanostruktury v kondensirovannykh sredakh» [Fullerenes and nanostructures in condensed media, materials of the XI Intern. scientific. conf. 24–26 November, Minsk, 2020]. Minsk, A.V. Luikov Institute of Heat and Mass Transfer of the National Academy of Sciences of Belarus, 2020, pp. 21–26 (in Russian).
6. Hao T. Electrorheological Fluids. The Non-aqueous Suspensions. Vol. 22. 1st ed. Cambridge, Massachusetts, USA, Elsevier Science, 2005. 578 p. https://doi.org/10.1016/s1383-7303(05)x8015-2
7. Murashkevich A. N., Alisienok O. A., Zharskii I. M., Korobko E. V., Novikova Z. A. The effect of the synthesis conditions of aluminum-modified nanosized titanium dioxide on the efficiency of its use in electrorheological dispersions. Kolloidnyi zhurnal = Colloid Journal, 2017, vol. 79, no. 1, pp. 87–93. https://doi.org/10.1134/s1061933x17010100
8. Tang H., He J., Persello J. Giant electrorheological effects of aluminum-doped TiO2 nanoparticles. Particuology, 2010, vol. 8, no. 5, pp. 442–446. https://doi.org/10.1016/j.partic.2010.07.007
9. Kniep R. Orthophosphates in the system Al2O3-P2O5-H2O. AngewandteChemie International Edition in English, 1986, no. 25, no. 6, pp. 525−534. https://doi.org/10.1002/anie.198605251
10. Kolb E. D., Grenier J. C., Laudise R. A. Solubility and Growth of A1PO4 in a hydrothermal solvent: HCl. Journal of Crystal Growth, 1981, vol. 51, no. 2, pp. 178−182. https://doi.org/10.1016/0022-0248(81)90299-2
11. Kolb E. D., Barns R. L., Laudise R. A., Grenier J. C. Solubility, crystal growth and perfection of aluminium orthophosphate. Journal of Crystal Growth, 1980, vol. 50, no. 2, pp. 404−418. https://doi.org/10.1016/0022-0248(80)90088-3
12. Bothe Jr. J. V., Brown P. W. Reactivity of alumina toward phosphoric acid. Journal of the American Ceramic Society, 1993, vol. 76, no. 9, pp. 2353–2358. https://doi.org/10.1111/j.1151-2916.1993.tb07776.x
13. Melikhov I. V. Physicochemical evolution of solids. Moscow, BINOM. Laboratoriya znanii Publ., 2006. 309 p. (in Russian).
14. Eshchenko L. S., Paniatouski A. V. Preparation of microcrystalline hydrated aluminum orthophosphate. The latest research in modern science: experience, traditions and innovations: Collected scientific articles of the X International scientific conference on February 18–19, Morrisville, NC, USA, 2020. Lulu Press, Morrisville, NC, USA, 2020, pp. 21–26.
15. Kotova N. P., Ivanov L. P. Stability of strontium aluminophosphates in the system SrO-Al2O3-P2O5-H2O at T = 25–350 °C and P = Psat – 500 bar. Geochemistry International, 2000, vol. 38, pp. 138−143.
16. JCPDS International Centre for Diffraction Data. Available at: https://www.icdd.com/
Review
Views: 673
Email this article 