Dissolution of nickel in non-oxidizing aqueous acid solutions

摘要

Fairly pure metallic nickel may be efficiently dissolved in non-oxidizing acid. If the nickel includes individual pieces longer than 0.5 mm in any linear dimension, oxidizing agent is preferably added from the beginning of dissolution, while if the nickel is powdered so that no single piece has a linear dimension longer than 0.35 mm, oxidizing agent is preferably added only after most of the originally supplied nickel has been dissolved. After oxidizing agent is added, most or all of the remaining undissolved nickeliferous solid will then dissolve. The temperature of the reaction mixture of acid liquid and solid nickel preferably is room temperature at the beginning of dissolution but is raised in steps to a final value of at least 65° C. and maintained at that temperature for several hours.