| 摘要 |
<p>PURPOSE:To separate easily and efficiently reduced black consisting of noble metals without dangerous handling by reducing a soln. contg. two or more kinds of noble metal ions under acidic conditions followed by filtration. CONSTITUTION:A soln. contg. ions of Pt, Pd and Rh and ions of Fe, Ni, etc. and Al, etc. as amphoteric elements is adjusted to pH 0-3.5 and reduced at 85 deg.C with one or more kinds of hydrazine cpds. selected from hydrazine hydrate, hydrazine sulfate, hydrazine hydrochloride, etc. By the reduction the elements other than the noble metals are left in the soln. in the form of ions, and the large particle noble metals are separated as reduced black. When this black contains Pd, nitric acid is first added to dissolve the Pd as palladium nitrate and filtered. A fused salt is then added to the resulting filtrate reduced black to metl the black, and the Rh is dissoled in water as rhodium sulfate, which is separated from the Pt.</p> |
