INFLUENCE OF STRUCTURAL FEATURES OF CHRYSOTYLE CRYSTALS ON THE ACTION OF THE SYSTEM OF CHRYSOTYLE AND SULFURIC ACID

The nature of the interactions between chrysotile and stoichiometrically necessary amounts (SNA) of sulfuric acid calculated in relation to the amount (molar) of magnesium contained in chrysotile – Mg₆[Si₄O₁₀](OH) has been studied. It has been shown that when using solutions containing sulfuric acid HCl (0-0.3), the amount of magnesium found in the solution corresponds to a proportional amount of the acid used. It was found that the output of magnesium into the solution slows down in the range of SNA (0.3-0.5). Proportionally, the dissolution of magnesium is restored in the range of SNA (0.5-0.7). However, the yield of magnesium in solution does not exceed 76% of its content in chrysotile due to the formation of polysilicon acid (SiO₂·nN₂O) in an acidic medium. The layer formed on the surface consisting of polysilicon acids is the main factor inhibiting the transition of magnesium into solution.

It was revealed that the amount of magnesium passing into solution depends not only on the concentration of acid, but also on the density of the layered structure of chrysotile. The conclusions are based on the results of chemical and X-ray phase studies of reaction products occurring during the dissolution of chrysotile asbestos in solutions of sulfuric acid H₂SO₄.

Based on results of the study, it was shown that the dissolution of magnesium silicates, the composition of which of minerals (chrysotile, lizardite, antigorite) of the serpentinite group with the general formula Mg₆[Si₄O₁₀](OH)₈ in acids depends not only on the patterns of acid-base interactions occurring under these conditions, but also on the structural features of the serpentinite crystal lattice.

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