METHOD OF LITHIUM TETRAFLUOROBORATE PRODUCING Russian patent published in 1994 - IPC

FIELD: chemical technology. SUBSTANCE: initial powder of preliminary dried lithium fluoride is placed into hermetically sealed reactor (residual pressure is 2 kPa) and heated up to 295-430 C. Then evacuation of reactor is repeated, and boron trifluoride is fed up to pressure 0.1-2.5 MPa. Synthesis of lithium tetrafluoroborate is accompanied with intensive uptake of boron trifluoride. Consumption of latter is compensated by continuous feeding of boron trifluoride into reactor. After pressure fall reactor is cooled up to 50-100 C. Yield of LiBF₄ is 99.5-99.9%, content of LiF in product is 0.07- 0.11%. EFFECT: improved method of synthesis. 1 tbl