POWDER-LIKE TITANIUM DIOXIDE OBTAINED BY FLAMEHYDROLYSIS Russian patent published in 2009 - IPC C01G23/07 

FIELD: chemistry.

SUBSTANCE: obtained by flame method titanium dioxide is in form of aggregates of primary particles and possesses BET surface area equal from 20 to 200 m²/g, semi-width (SW) [nm] of primary particles distribution, SW=a×BET^f, where a= 670×10^-9 m³/g and -1.3 ≤ f ≤ -1.0. Fraction of particles with diameter exceeding 45 mcm, is within range from 0.0001 to 0.05 wt %. Powder-like titanium dioxide is obtained by method in which titanium tetrachloride is evaporated at temperature lower than 200°C, vapours get into mixing chamber by means of wet gas-carrier. Independently on this, oxygen, primary air, which can optionally be enriched with oxygen and/or preliminary heated, and vapour are supplied into mixing chamber. Obtained reaction mixture is burnt in reaction chamber. Secondary air is additionally supplied into reaction chamber. Obtained powder-like titanium dioxide is separated from gaseous substances and processed with vapour.

EFFECT: possibility of obtain easily dispersible highly-pure titanium dioxide with reduced content of coarse-grain fraction on industrial scale.

20 cl, 2 dwg, 4 tbl, 23 ex