METHOD OF PROCESSING SOLUTION CONTAINING FLUOROTITANIC ACID AND IMPURITY MINERALS Russian patent published in 2004 - IPC

FIELD: inorganic compounds technology.

SUBSTANCE: invention relates to processing solutions containing fluorotitanic acid and impurities, in particular in preparation of titanium dioxide pigment, high-purity titanium dioxide, and others. Solution containing fluorotitanic acid and impurity minerals is concentrated to content of fluorotitanic acid (on conversion to TiO₂) not higher than 800 kg/m³ and mixed with organic solvent in the form of oxygen-containing extractant, namely aliphatic C₇-C₁₂-alcohols, preferably 2-ethylhexanol, 1-octanol, 2-octanol, or their mixtures. Resulting mixture is subjected to 3-6-fold extraction until content of fluorotitanic acid in raffinate achieves 200-300 kg/m³ (as TiO₂). Ratio of organic to aqueous phase (2-5):1. These phases are separated from each other to give fluorotitanic acid extract and raffinate. Part of the latter is returned into concentration operation. Acid is the re-extracted 3-5 times with aqueous re-extractant at organic-to-aqueous phase ratio (1-5):1 to give re-extract in the form of purified fluorotitanic acid solution. Aqueous re-extractant can be purified water, initial solution evaporation condensate, or solution of purified fluorotitanic acid. Regenerated organic phase is returned into extraction stage.

EFFECT: increased fluorotitanic acid purification degree.

9 cl, 3 dwg