METHOD OF OBTAINING ISOTOPE-ENRICHED VITREOUS SILICON DIOXIDE Russian patent published in 2019 - IPC C01B33/12 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing isotope-enriched vitreous silicon dioxide SiO₂, enriched with silicon isotopes ²⁸Si or ²⁹Si or ³⁰Si, which can be used to produce silicon isotopes, optical materials, fiber-optic guides and films from isotopically-rich silicon dioxide. Method includes synthesis of isotope-enriched silicon alkoxide Si(OR)₄ (R – CH₃, C₂H₅, i-C₃H₇) during reaction of inorganic compounds, such as isotopically-enriched silicon tetrachlorides ²⁸SiCl₄, ²⁹SiCl₄, ³⁰SiCl₄, with anhydrous alcohol of general formula R-OH (R – CH₃, C₂H₅, i-C₃H₇) at temperature of 20–50 °C and 2-4-fold excess of alcohol relative to stoichiometric ratio, hydrolysis of silicon isotope-rich alkoxide, drying and thermal treatment of obtained gel of hydrated isotopically-enriched silicon dioxide.

EFFECT: invention increases output of isotope-enriched vitreous silicon dioxide to 96 %, simplifies and increases efficiency of the method, eliminates the need to use complex equipment and large amounts of scarce isotopic enriched substances and safety of the process.

5 cl, 2 ex