| 摘要 |
FIELD: chemistry. ^ SUBSTANCE: invention relates to production of strontium fluoride used in production of ceramics, fluoride glass and fibre-optic materials. Before fluorination, aqueous strontium nitrate solution is purified from metal impurities by mixing with aluminium nitrate nano-hydrate at a rate of 50-80 rpm, where the said aluminium nitrate nano-hydrate is taken in amount of 2% of the weight of anhydrous strontium nitrate. The formed solution is leached to pH 8.0-8.2, heated to 60-70C and the aqueous solution is then separated from the precipitate on a vacuum filter. The purified aqueous strontium nitrate solution is fed into a reactor for the fluorination step together with 5-25% hydrofluoric acid and with 10% stoichiometric excess. The process is carried out at temperature 50-60C while stirring at a rate of 700-900 rpm. The filtered product is washed with water and then dried at temperature 120-150C. ^ EFFECT: invention enables to obtain high-purity strontium fluoride containing over 99,9 wt % basic substance, which meets requirements for fibre-optic products. ^ 4 cl, 2 ex |
