Institute of Fine Chemical Technologies, Moscow Technological University, Moscow, Russia:
L. E. Lozhkina, Master’s Degree Student
M. M. Sadykova, Post Graduate Student, e-mail: sadykova.mm@mail.ru
G. V. Zimina, Leading Researcher

Lomonosov Moscow State University, Moscow, Russia:

F. M. Spiridonov, Assistant Professor of a Chair of Inorganic Chemistry

We investigated the conditions of strontium release during complex processing of apatite concentrate. By using nitric acid technology, we can release strontium in a nitrate form on the first stage of concentrate processing due to desalting effect of nitric acid. We also investigated the dependence of quantitative release of strontium from a nitric acid concentration. According to this, 80–97% of strontium nitrate is precipitated with 45–60% of nitric acid; after washing with water and 45% HNO₃ for removing of calcium residue, the parameters of strontium nitrate lattice meet the data of X-ray files. Isolated strontium nitrate was used to obtaining strontium carbonate by interaction with ammonium carbonate. Nowadays, strontium carbonate is the most demanded product. Our article shows the principle flowsheet of strontium nitrate extraction and its processing in carbonates. When developing the strontium extraction technology, we considered the fact that the release of strontium and other valuable components (rare metals and fluor), contained in apatite, should be a side process, which doesn’t disturb the technology and the quality of the obtained basic product – phosphorous fertilizers.

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