| 摘要 |
1482173 Finely divided oxides KRONOS TITAN-GmbH 7 Oct 1974 [8 Oct 1973] 43413/74 Headings C1A and C1N Finely divided solid oxides are made by (a) reacting in a reaction chamber the corresponding chloride in the gas phase at high temperatures and super-ambient pressure, preferably not exceeding 1À4 atmospheres gauge, with O 2 or O 2 -containing gas which has been heated in the chamber by burning a gaseous fuel (b) separating the finely divided solid oxide from the reaction gases and (c) passing the reaction gases without further compression to a chlorination plant at a super-ambient pressure which is the residual pressure after steps (a) and (b) as at least part of the Cl 2 source material for forming said corresponding chloride by the reaction of chlorine with an oxide or oxidic material. The reaction mixture is preferably cooled before separation of the oxide in a heat-exchanger, preferably to 200-400‹ C. The oxide separation may be a wet separation but is preferably effected in a filter and/or cyclone. The process is suitable for the manufacture of oxides of Si, Al, Zr and expecially Fe and Ti. In a preferred embodiment for the manufacture of TiO 2 small quantities of other substances which promote the formation of pigment, e.g. AlCl 3 , steam or alkali metal compounds may be introduced into the oxidation chamber. |
