Summary
Thermal reactions in natural fluorapatite or fluorcarbonate apatite and ammonium sulfate mixtures with mole ratio 1:4 at calcination up to 500°C were studied by simultaneous thermogravimetry and FTIR analysis of the evolved gases. The composition of natural apatite has little impact on the release of NH3. Upon the evolution of NH3 nitrous oxides were found in minor amounts. The release of SO2 at temperatures above 400°C is more intensive and occurs at lower temperatures in the case of fluorapatite than of carbonate containing apatites. Evolution of CO2 starts at 250°C with maximum at 350-360°C.
Article PDF
Similar content being viewed by others
Explore related subjects
Discover the latest articles, news and stories from top researchers in related subjects.Avoid common mistakes on your manuscript.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Tõnsuaadu, K., Pelt, J. & Borissova, M. Monitoring of the evolved gases in apatite-ammonium sulfate thermal reactions. J Therm Anal Calorim 80, 655–658 (2005). https://doi.org/10.1007/s10973-005-0709-3
Issue Date:
DOI: https://doi.org/10.1007/s10973-005-0709-3