| 摘要 |
<PICT:0938969/III/1> Zirconium or hafnium tetrachloride is converted to halogenozirconate or halogenohafnate, prior to reduction to metal with magnesium, in the apparatus shown in Fig. 1. Reactor 1 contains two crucibles 3, 4, located one above the other, their temperatures being independently controlled by heating coils 5, 6. Tetrachloride is placed in crucible 3, and the appropriate salt, e.g. sodium chloride, together with magnesium, in crucible 4. After purging with argon or helium, crucible 4 is heated to a temperature at which the tetrachloride salt system will be liquid, but below the melting point of magnesium, and crucible 3 is then heated to volatilize tetrachloride which diffuses into the salt until saturation is reached. Heating of crucible 3 is then discontinued, cover 21 closed, and crucible 4 heated to 800 DEG C. to initiate the reduction reaction. |
