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Synthesis of MgAl 2 O 4 from a stoichiometric mixture of aluminum and magnesium nitrates by its burning with urea, glycine, sugar, and mixtures of these as a fuel was studied.A transparent ceramic based on MgAl 2 O 4 is a good alternative to the expensive and diffi cultly reproducible single-crystal MgAl 2 O 4 spinel. Optical applications of the transparent ceramic includes IR windows and inert laser shutters [1]. It is known that good properties of a ceramic result from the adequate choice of synthesis method and sintering conditions, being also determined by favorable properties of the starting powder. It is impossible to obtain a good, homogeneous, pore-free ceramic suitable for optical applications without using a highly active, pure, and unagglomerated powder.It was shown in [2, 3] that the burning method is promising for production of highly pure homogeneous crystalline powders of the aluminomagnesium spinel at comparatively low temperatures with lower energy expenditure. In addition, powders produced by this method retain their nanostructure even upon sintering, which is highly important for fabrication of superelastic materials.A study of MgAl 2 O 4 synthesis in an electric furnace at 500°C in the course of 5 min with urea [2] demonstrated that parameters of the powder synthesized depend on the charge of the starting substances. For example, with the mass of the fi nal product raised from 2 to 100 g, the specifi c surface area of the powder decreases from 126 to 8.1 m 2 g -1 . This can be attributed to the high adiabatic temperature generated as a result of increasing accumulation of heat at larger single-portion charges.The goal of our study was to obtain Mg Al 2 O 4 by the burning method. EXPERIMENTALAs starting materials served magnesium nitrite Mg(NO 3 ) 2 ·6H 2 O, aluminum nitrite Al(NO 3 ) 3 ·9H 2 O, urea, glycine (all of analytically pure grade), and sugar. A mixture of the starting components to obtain 5-10 g of MgAl 2 O 4 was prepared by mixing of stoichiometric amounts of Al(NO 3 ) 3 ·9H2O and Mg(NO 3 ) 2 ·6H 2 O and a prescribed amount of the fuel in a Tefal household blender. The mixture was thermally treated in singleor double-stage modes: (1) by calcination in alundum crucibles in a muffl e furnace heated at a rate of 15 deg min -1 to 800°C in the course of 1 h and (2) by preliminary drying in glass vessels in a drying box at 300°C for 1 h, mixing in a blender, and calcination in a muffl e furnace under the same conditions.The phase composition of the powders was determined by X-ray phase analysis on a DRON-12 diffractometer (Cu Kα radiation and graphite monochromator), with a counter motion rate of 2 deg min -1 . The phases were identifi ed using the JCPDS database. The specifi c surface area of MgAl 2 O 4 powder samples was determined by the method of thermal desorption of nitrogen on a FlowSorb II 2300 laboratory electronic specifi c-surface-area and porosity meter. The average crystallite size was calculated by the Debye-Scherrer formula d = 0.94λ/ βcos θ, where λ for Cu K is 0.15406 nm;...

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