| US 7,476,378 B2 | ||
| Process for producing titanium dioxide | ||
| Narayanan Sankara Subramanian, Hockessin, Del. (US); Richard P. Bernard, Gulfport, Miss. (US); Yung-Hsing Samson Hsu, Gulfport, Miss. (US); Charles David Musick, Waverly, Tenn. (US); Kunle Ogunde, Wilmington, Del. (US); and James Nelson Tilton, Landenberg, Pa. (US) | ||
| Assigned to E.I. DuPont deNemours & Company, Wilmington, Del. (US) | ||
| Filed on Oct. 27, 2005, as Appl. No. 11/260,058. | ||
| Prior Publication US 2007/0172414 A1, Jul. 26, 2007 | ||
| Int. Cl. C01G 23/00 (2006.01); C01G 23/047 (2006.01); C01G 23/07 (2006.01); B01J 21/06 (2006.01); B01J 37/07 (2006.01); B01J 37/12 (2006.01); B01J 37/14 (2006.01) | ||
| U.S. Cl. 423—613 [423/69; 423/75; 423/76; 423/79; 423/81; 423/84; 502/350] | 20 Claims |
| 1. A process for producing titanium dioxide, comprising:
a) providing a quantity of liquid titanium tetrahalide for reacting with an oxygen-containing gas;
b) vaporizing a first portion of the liquid titanium tetrahalide and reacting the titanium tetrahalide vapor and the oxygen-containing
gas, in a first stage of a reaction zone, the reaction zone temperature being sufficient to form a reaction product at least
containing titanium dioxide and oxygen-containing gas and passing the reaction product to at least one additional stage of
the reaction zone; and
c) charging at least one additional portion of the liquid titanium tetrahalide directly into the at least one additional stage
of the reaction zone at a temperature below the boiling point of the titanium tetrahalide, at the charge pressure of the titanium
tetrahalide, to cool the titanium dioxide and to react with the oxygen-containing gas to form additional titanium dioxide,
under conditions sufficient to form a product substantially free of titanium tetrahalide.
|