Entrained-flow chlorination of titaniferous slag to produce titanium tetrachloride

Preparation of titanium tetrachloride was investigated by chlorination of a low-grade titaniferous slag in an entrained-flow reactor over the 550 to 1100 °C temperature range. Chlorination rates were highly dependent on the reactivity of the carbon used in the chlorination reaction. Use of a lignitic char resulted in the higher chlorination rates, whereas use of petroleum coke resulted in lower reaction rates. Use of bituminous coke gave intermediate chlorination rates. Above 700 °C, the chlorination reaction rate is controlled by mass transfer. Chlorine is completely reacted in 2.5 seconds at 1100 °C using slag/char feedstocks of 7-µm median particle diameter, with 10 to 25 pct excess carbon and 15 to 20 pct excess slag.