METHOD OF OBTAINING POTASSIUM FLUOROTHANALATE FROM TANTALUM-CONTAINING SOLUTIONS Russian patent published in 2017 - IPC C01G35/02 C22B34/24 C22B3/04 

FIELD: chemistry.

SUBSTANCE: method involves preparing the initial fluorotantal solution, heating it, precipitating the fluorotantalate with a potassium-containing reagent, cooling and holding the pulp to crystallise potassium fluorotantalate, settling the pulp, decanting it, repulping the potassium fluorotantalate with washing solution, filtering the resulting pulp, and drying the crystals of potassium fluorotantalate. Potassium hydroxide is used as a potassium-containing reagent. Sedimentation of fluorotantalate from the initial solution is carried out in two stages with holding between them. Repulpation of potassium fluorotantalate is carried out in two stages with a washing solution containing 1% HF + 1% KF with decantation on the first stage and filtration on the second stage. Drying of crystals of potassium fluorotantalate is carried out in two stages at different temperatures at each stage.

EFFECT: obtaining crystalline fluorotantalate of high purity potassium, ensuring the utilisation of fluorine during the processing of tantalum niobates and eliminating the multi-operation process of recrystallization.

5 cl, 2 dwg, 6 tbl