| Popis: |
By means of the following solid oxide galvanic cells: Pt,Ni + NiO¦O 2− ¦SrSO 4 + SrS,Au and Pt,Fe + FeO¦O 2− ¦SrSO 4 + SrO,Au the equilibrium oxygen pressure was determined for the reactions SrS + 2O 2 → SrSO 4 and SrSO 4 → SrO + SO 2 + 1 2 O 2 Results obtained under “closed cell” conditions suggest that the Gibbs free energy change for the reaction of sulphate decomposition into SrO and the gas phase is much lower than that reported in thermochemical tables. For this reaction, experiments yielded Δ G 0 T = 882550−438.3 T J mol −1 in the temperature range 973–1273 K. Conditions of phase equilibria for the Sr-S-O system at 1273 K were suggested, and kinetics of the reduction reaction SrSO 4 +4 H 2 → SrS + 4 H 2 O were investigated in the temperature range 1073–1273 K. |
