The widespread use of various substances in the flotation of minerals clogs wastewater, which, poisoning reservoirs, endangers the normal existence of wildlife.

The kinetics of dissolution and methods of phase analysis of antimony compounds have been studied repeatedly. To study the kinetics of Sb₂S₃ and Sb₂O₃ dissolution in KOH solutions, polydisperse samples of these antimony compounds (analytical grade) were taken with a view to using them for phase analysis. Using the low temperature inert gas adsorption method, the specific surface area was determined for Sb₂S₃ and Sb₂O₃. The kinetics of the interaction of Sb₂O₃ with solutions follows the laws of first order reactions under the conditions of the diffusion regime of the dissolution process. The dissolution of Sb₂O₃ and Sb₂S₃ in solutions cannot be used for selective dissolution in phase analysis. ...

Hydrochloric and nitric acids, commonly used to separate oxidized and sulfide bismuth compounds, do not permit quantitative separation of oxidized and sulfide bismuth minerals. ...

High refractoriness (2715°), slag resistance, low thermal and electrical conductivity at high temperatures, mechanical strength and thermal stability under sharp temperature fluctuations make zirconium dioxide a very valuable source of highly refractory material, especially after it was discovered that cracking during heating of products made of pure zirconium dioxide, caused by the transformation of one modification into another at a temperature of 1000°, can be eliminated by adding more than 4% magnesium or calcium oxide, which form stable solid solutions with zirconium dioxide. In the Soviet Union there are numerous deposits of zirconium ores, ensuring their industrial use. As for magnesium oxide and calcium oxide, these source materials are available in unlimited quantities. All this shows that the study of the ternary system ZrO₂—MgO—CaO has not only theoretical but also significant practical interest.