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[References: 16 tit.]

Adding copper nitrate Cu(NO3)2 is known to activate the oxidation of coal and lignite. In the present work, the change in its activating properties with increase in the heating rate is studied. The Cu(NO3)2 is first dissolved in a 50/50 (by volume) mixture of ethyl alcohol and water. Then it is applied to the fuel by steeping, to a content of 5 wt %. Activated oxidation is studied by thermal analysis, with different heating rates (2.5, 10, 20, and 40°C/min) in the temperature range 25–1000°C, at atmospheric pressure. With increase in heating rate, the catalytic effect of the additive is intensified: the initial (30–115°C) and final (85–180°C) oxidation temperatures fall, with increase in the maximum reaction rate. Mass-spectrometric analysis of the gaseous oxidation products shows that, in the presence of copper nitrate, increase in the heating rate leads to greater CO2 emission, with shorter oxidation time. The dependence of the activation energy on the degree of fuel conversion is determined by the Friedman method. The decrease in the mean activation energy when using Cu(NO3)2 is ~14 kJ/mol for lignite and ~35 kJ/mol for coal.