METHOD OF PRODUCING TITANIUM TANNING AGENT Russian patent published in 2013 - IPC C14C3/04 C14C3/00 C01G23/00 

FIELD: chemistry.

SUBSTANCE: titanium hydroxide containing 30-80% TiO₂ is mixed with ammonium sulphate in weight ratio of 1:0.05-0.2 with respect to TiO₂ and the obtained mixture is treated with sulphuric acid with concentration of 600-800 g/l H₂SO₄ with transfer of titanium into the solution. Ammonium sulphate is added to the titanium solution in weight ratio TiO₂:(NH₄)₂SO₄=1:3.5-5.5 to precipitate a double salt of ammonium and titanium sulphate. The precipitate is separated by filtering and washed with saturated ammonium sulphate solution with concentration of 400-450 g/l. The end product is obtained - a titanium tanning agent and a filtrate which contains ammonium sulphate which can be used when adding ammonium sulphate to the titanium solution. The method enables to obtain a titanium tanning agent from titanium hydroxide with high (94.7-97.6% TiO₂) extraction of titanium and low content of iron impurities (0.01-0.025% Fe₂O₃).

EFFECT: method is less energy-consuming, cheap and is characterised by low consumption of ammonium sulphate.

3 cl, 4 ex