DEVICE FOR GROWING MIXED CRYSTALS OF COBALT-NICKEL-POTASSIUM SULPHATE FOR OPTICAL FILTERS OF ULTRAVIOLET RANGE Russian patent published in 2020 - IPC C30B7/08 C30B29/10 G02B5/20 G02B1/02 

FIELD: chemistry.

SUBSTANCE: invention relates to growth of crystals, particularly growing of mixed monocrystals K₂(Co,Ni)(SO₄)₂x6H₂O (KCNSH) from aqueous solutions and can be used in optical instrument-making for manufacturing of solar-blind filters. Device for growing mixed crystals of cobalt-nickel-potassium sulphate contains a crystalliser with a sealed cover and primer 7 fixed thereon, placed in a heat assembly with the possibility of turning about the horizontal axis through 180 °C during growth, note here that heat assembly is composed of shaft furnace with two independent heaters 6, 9, while crystalliser consists of top 3 and bottom 8 – growth parts differing by volume as 100/1, with diameter of lower part corresponding to size of produced crystal. Result is due to fact that bulk of solution is in upper part of crystallizer at temperature above liquidus (in non-saturated state), and the solution in the lower part of the crystalliser (growth part which is much smaller in volume) is at temperature below the liquidus, which enables to considerably (up to 100 times) reduce the volume of the solution which is in a supersaturated state.

EFFECT: performing crystallizer from two parts with different volumes and its installation in thermal assembly with two heating zones allows preserving metastability of solution for a long period of time and preventing occurrence of spontaneous crystals.

1 cl, 3 dwg