- Tytuł:
- Time constraints on experimental studies of lead apatites
- Autorzy:
-
Topolska, Justyna
Bajda, Tomasz
Puzio, Bartosz
Manecki, Maciej
Kozub-Budzyń, Gabriela - Powiązania:
- https://bibliotekanauki.pl/articles/2058621.pdf
- Data publikacji:
- 2019
- Wydawca:
- Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
- Tematy:
-
pyromorphite
vanadinite
experimental mineralogy
dissolution
solubility synthesis - Opis:
- The paper presents the results of experimental studies on the synthesis and thermodynamic stability of selected Pb-apatites in terms of criteria determining termination of the experiments. Based on the case study, we indicate difficulties in analysing the obtained experimental data. Time-resolved sampling of precipitate formed during a dropwise synthesis of pyromorphite was performed and the results were compared to the literature data. It has been concluded that the Ostwald ripening time for synthesized solids depends primarily on the chemical composition of the intended Pb-apatite phase. We presented that heterogeneity of precipitate affects its dissolution in terms of repeatability of the results and equilibrating time. A unique 9-year-long experiment on vanadinite stability at a pH range from 2.0-6.0 revealed that among all tested dissolution conditions only the reactions at the pH = 3.5 can perform as the basis for some thermodynamic calculations. It has been concluded that the rate of phase transitions in the Pb-apatites group can be misleading in terms of determining the equilibrium of the system, and the experimental setup designed particularly to provide reliable controls in this aspect should be involved. Means in this respect have been proposed.
- Źródło:
-
Geological Quarterly; 2019, 63, 4; 721--728
1641-7291 - Pojawia się w:
- Geological Quarterly
- Dostawca treści:
- Biblioteka Nauki
Artykuł