Galina Sádovská

Modified stepwise method for determining heat capacity by DSC

The methods of heat capacity data determination from differential scanning calorimetry measurements are described. The negative effects increasing uncertainty of heat capacity determination are mentioned. Modified stepwise method was described and verified using molybdenum, copper, and gold standards. Modified stepwise method provides better accuracy of Cp values compared to continuous and stepwise method.

FeOx/Al2O3 catalysts for high-temperature decomposition of N2O under conditions of NH3 oxidation in nitric acid production

The catalytic activity of a series of FeOx/Al2O3 prepared under various conditions was evaluated for high temperature decomposition of N2O (HT-deN2O) in a complex gas mixture produced by oxidation of ammonia. Thus the relevant step in the industrial nitric acid production process was simulated. The catalyst stability during long-term exposure (12 days) to reaction conditions relevant to HT-deN2O was studied. Both fresh and aged FeOx/Al2O3 exhibited more than 90% conversion of N2O in the 750–900 °C temperature range. Structural analysis showed that the prepared FeOx/Al2O3 catalysts contained various proportions of δ, θ and α alumina phases and up to four individual iron species. In the δ and θ Al2O3 phases, well stabilized Fe(III) in Td or Oh coordination was identified as the active species in HT-deN2O.