| 摘要 |
<p><PICT:0828238/III/1> Titanium, zirconium, cerium, hafnium, or thorium are obtained by heating an oxidic ore thereof, under elevated pressure in excess of 2 atms., with sufficient carbon to convert available oxygen in the ore to carbon monoxide and with sufficient additional CO for the compound M(CO)7 to be formed, where M is the metal, distilling off the M(CO)7 formed, and dissociating the distilled M(CO)7 by heating under atmospheric pressure to precipitate the metal and release CO. Finely divided rutile and activated carbon is charged through 12 into pressure vessel 10, and is agitated by stirrer 11, while being heated to 300-800 DEG C. by burners 16 or resistance coils. Excess CO enters at 13 and the pressure should be 2-10 atmospheres, which may be maintained by CO only or by addition of inert gas, e.g. helium or argon. Preferred conditions are 400 DEG C. at 4 atms. When the speed of reaction has fallen appreciably, as indicated by CO absorption, the temperature is raised 50-100 DEG C. to distil the Ti(CO)7 into precipitation vessel 17 which is isolated by valve 20. The temperature is raised a further 50-100 DEG C. by burners 24, when titanium is deposited. The CO is purged through 22 by inert gas, e.g. helium or argon, entering at 21 and may be recycled to pressure vessel 10. A cascade of precipitation vessels may be used to ensure complete recovery of the titanium.</p> |
