Funct. Mater. 2020; 27 4: 820-826.


Influence of crystal hydrate water on the process and products of heat treatment of magnesium-manganese(II) dihydrogen phosphates

N.M.Antraptseva, N.V.Solod, O.O.Kravchenko

National University of Life and Environmental Sciences of Ukraine, 15 Geroev Oborony Str., 03041 Kyiv, Ukraine


It has been established that crystalline water affects the change in the quantitative composition of the products and the characteristics of the process as a whole during the heat treatment of Mg1-xMnx(H2PO4)2·4H2O tetrahydrates. The maximum content of free mono- and polyphosphate acids, which are isolated in the composition of the intermediate heat treatment products during the thermolysis of tetrahydrates, is 1.6 times higher than in dihydrates with the same ratio of cations. The degree of conversion of the monophosphate anion to polyphosphate in the heat treatment products of tetrahydrates is 1.1-1.2 times greater than at the similar stages of the thermolysis of Mg1-xMnx(H2PO4)2·2H2O dihydrates. The maximum degree of polycondensation is also higher for polyphosphates in the composition of the heat treatment products of tetrahydrates (n‾ = 8 for Mg0.5Mn0.5(H2PO4)2·4H2O, n‾ = 7 for Mg0.5Mn0.5(H2PO4)2·2H2O).

dihydrogen phosphates, tetrahydrates, crystalline hydrate water, heat treatment.
1. A.Q.Acton, Phosphates - Advances in Research and Applicationm, Atlanta, Georgia (2013).
2. T.Kanazawa, Inorganic Phosphate Materiales, Elsevier, New York (1989).
3. L.Shchegrov, Phosphaty Dvuhvalentnyh Metallov. Naukova Dumka, Kiev (1987).
4. Y.Chang, N.Shi, S.Zhao et al., ACS Appl. Mater. Inter., 34, 22534 (2016).
5. L.Robertson, Etude de Pigments Thermochromes Autour du Cobalt II. Materiaux, Universite Sciences et Technologies, Bordeaux (2010).
6. B.Boonchom, S.Maesiri, S.Youngme, C.Danvirutai, Solid State Sci., 11, 485 (2009).
7. N.Antraptseva, N.Solod, R.Zhyla, Functional Materials, 25, 167 (2018).
8. L.Shchegrov, N.Antraptseva, V.Kopilevich, Phosphorus Sulfur, 51, 149 (1990).
9. M.Trojan, D.Brandova, Thertnochim. Acta, 161, 11 (1990).
10. L.Shchegrov, N.Antraptseva, I.Ponomareva, J. Inorg. Chem., 33, 118 (1988).
11. V.Pechkovskiy, R.Melnikova, E.Dzyuba, J. Inorg. Chem., 24, 894 (1979).
12. V.Makatun, Chemistry of Inorganic Hydrates, Nauka i Tehnika, Moscow (1985) [in Russian].
13. N.Antraptseva, Ukr. Him. Zh., 63, 19 (1997).
14. R.Melnikova, V.Pechkovskiy, et al., Atlas of IR Spectra of Phosphates: Condensed Phosphates, Nauka, Moscow (1985) [in Russian]
15. JCPDS, Powder Diffraction Fill, Inorganic Phases, Swarthmere, USA (1986), card No.36-210, 21-1489.


Current number: