@article{Bochevskaya Ye., Karshigina Z., Abisheva Z. and Sharipova A._2020, title={Phosphoric Slag Leaching with Mineral Acids Process}, volume={29}, url={http://sersc.org/journals/index.php/IJAST/article/view/19243}, abstractNote={<p><em>The thermodynamic calculation was performed for the probability of the main slag components leaching reaction ∆G°<sub>T</sub> with mineral sulfuric (H<sub>2</sub>SO<sub>4</sub>), phosphoric (H<sub>3</sub>PO<sub>4</sub>), hydrochloric (HCl) and nitric (HNO<sub>3</sub>) acids, taking into account a phase and chemical compositions of the initial product. Gibbs energies were calculated for the reactions in the temperature range from 20 to 100 °C. It was found that the reactions were thermodynamically favorable and were almost not-reversible. The interaction of Fe<sub>2</sub>O<sub>3</sub> with hydrochloric acid was an exception. With the temperature increase from 60 to 100 °C, hydrolysis went due to the increase in the dissociation degree of water molecules affecting the results of hydrochloric acid treatment. Experiments on the phosphorus slag dissolution were performed with H<sub>3</sub>PO<sub>4</sub>, HCl and HNO<sub>3</sub> solutions in the concentration of 2 mol/dm<sup>3</sup>. The distribution of calcium, aluminum, and iron were analyzed over the slag leaching products. The choice of nitric acid as a leaching reagent was justified. A thermodynamic analysis of the reactions of the interaction of the slag rare-earth metals components with nitric acid was performed. The use of nitric acid in the analyzed temperature range from 50 to 100 °C was acceptable for all rare-earth components. For thermodynamic purposes reactions of rare-earth metals and their ions interaction with nitric acid were the most favorable for lanthanum sulfide, yttrium phosphate, lanthanum and neodymium phosphate, as well as for rare-earth metals carbonate ions. The Gibbs energy for these compounds was within from –424.93 to –36.16 kJ/mol. Rare-earth metals (REMs) remained in the cake by </em><em>~</em><em> 85% when phosphoric slag was leached with a HNO<sub>3</sub> solution in the concentration of 2 mol/dm<sup>3</sup>. It was found that the use of nitric acid as an opening reagent was favorable for the decomposition of the main components of phosphorus slag.</em></p&gt;}, number={08}, journal={International Journal of Advanced Science and Technology}, author={Bochevskaya Ye., Karshigina Z., Abisheva Z. and Sharipova A.}, year={2020}, month={May}, pages={899 - 911} }