| 摘要 |
<p>TITLE OF THE INVENTION NICKEL RECOVERY A nickel-containing residue such as coal ash remains after a carbonaceous material is gasified in the presence of a nickel catalyst. Nickel is recovered from the residue by adding an aqueous ammonia solution or aqueous solution containing ammonia and an ammonium salt to the residue to form a nickel ammine solution. Insoluble contents are separated from the nickel ammine solution, to which ammonia is further added to precipitate the nickel ammine.</p> |
