| 摘要 |
<p>1,191,767. Chlorinating titanium bearing materials. PPG INDUSTRIES Inc. 22 Nov., 1968 [7 Dec., 1967], No. 55506/68. Heading C1A. Titanium tetrachloride is prepared by chlorinating a titanium-bearing material in a fluidized bed, in the presence of a carbonaceous reductant and a metal source selected from magnesium, calcium, strontium, barium, cadmium and mixtures thereof. Amounts may be sufficient to increase the ratio of CO 2 to CO, both of which are produced during the reaction, but less than an agglutinating amount. Any fluidizable source of titanium is suitable for this process, especially a source containing in excess of 90% by weight of titanium dioxide. Rutile, especially Sierra Leone rutile, is particularly suitable for treatment. Particle size may be between 75 and 500 Á. The reductant may be coke, carbon monoxide, graphite, charcoal, carbon tetrachloride or phosgene. Carbon content may be 10-50% by weight of the total composition of the bed. The average particle size of the reductant may be between 100 and 900 Á. The temperature of the reaction is preferably above 500‹ C. The additives may be introduced as carbonates, sulphates, chlorides, oxides, phosphates, carbides or as the free metal. They may also be introduced in a second titanium-bearing material, provided that this material contains more of the additive than is present in the original titanium source. For example, Australian rutile may be added to Sierra-Leone rutile as a source of calcium and magnesium. The amount of additive may be between 0À001 and 0À35 weight per cent, based on the amount of titanium dioxide in the titanium-bearing material.</p> |
