| 摘要 |
<p>In the prodn. of Zr sponge by redn. of ZrCl4 with metallic Mg in which a deposit of Zr sponge together with Mg chloride is formed on the crucible wall, the Zr sponge, Mg chloride and residue of metallic Mg is removed from the bottom of the crucible. The crucible portion contg. the deposit which has been cut off, is again joined to the bottom part by welding, the crucible is charged with fresh metallic Mg and placed in the redn. vessel to reduce the Zr sponge deposit to Zr, of higher purity. The redn. reaction is carried out so that Zr sponge is deposited direct on the internal wall of the crucible or on a thin-walled cylinder which fits inside the crucible and lying close to the internal wall. The Zr sponge deposit and Mg chloride which are on the crucible wall of the cut off portion are kept in a dry condition until the portion is reunited with the lower part of the crucible by welding. The crucible can be used again and a greater yield of Zr is obtd.</p> |
