Method for making titanium dioxide with variable sinter activity

摘要

Crystalline titanium dioxide powder in the form of aggregated primary particles has BET surface area of 70-100 m 2>/g and rutile content of greater than 10-40%. An independent claim is included for preparation of the titanium dioxide powder introducing titanium tetrachloride vapor, and separately hydrogen, air or oxygen-enriched air into a mixing chamber; subsequently igniting the mixture in a burner and the flame is burned into a reaction chamber; subsequently separating the solid from gaseous substances, where the amounts used to achieve the BET surface area of 70-100 mVg and the rutile content of greater then 10-40% are selected so that the equation A=10 5>{[(TiCl 4x H 2)/(amount of airx total gas)]/BET]} (where A is 0.1-0.4) is obeyed and the unit of TiCl 4, H 2, amount of air and total gas is kmol/hour, that of the BET surface area is m 2>/g and that of A is 10 5> g/m 2>.