Synthesis of nanocrystalline magnesium oxide by thermolysis of magnesium citrate

Magnesium citrate, obtained by dissolving magnesium oxide in an aqueous solution of citric acid, turned out to be a decahydrate of the composition Mg₃(C₆H₅O₇)₂·10H₂O, which was established by the results of synchronous thermal analysis, X-ray diffraction and IR spectroscopy. It is shown that the thermal decomposition of this salt proceeds in three stages in the temperature ranges of 120–250, 250–370 and 370–550 °C to form nanocrystalline magnesium oxide with grain sizes from 7 to 23 nm.