Figure 1A:
Normalized DTA-signals as a function of the temperature for hydromagnesite decomposition under helium. Experimental data are represented as symbols, solid lines represent the calculated signals. The values of the heating rate in °C/min are marked on the curves.

Figure 1B:
Normalized DTA-signals as a function of time for hydromagnesite decomposition under helium. Experimental data are represented as symbols, solid lines represent the calculated signals. The values of the heating rate in °C/min are marked on the curves.

The TG and DTA data collected during non-isothermal decomposition of hydromagnesite with a rate of 2.5, 5, 7.5, 10 and 15.5 K/min were used for the determination of the kinetic parameters used later for the prediction of the reaction extent. The experimental conditions such as sample mass, atmosphere (He) and gas flow rate (50 ml/min) were identical in all experiments. In Figs. 1A-B, the experimental data of the DTA signals are presented and compared with the calculated curves. For each DTA scan, a tangential area-proportional baseline correction has been carried out. It is usually necessary to correct the measuring values of the baseline for all differential signal types, like DTA and/or DSC measurements. This is especially necessary when the reaction is characterized by a large difference of the specific heats of substrate and products.