| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method for removing iron, niobium, tungsten, molybdenum, oxygen, carbon, or the like, which are get mixed in scrap, such as waste pieces of material, machining chips and surface-grinding-wheel swarf, generated in the course of a target-manufacturing process by a relatively simplified step and recovering high-purity tantalum reusable as a tantalum target at a low cost and also to provide a target obtained by using this high-purity tantalum and to prepare a thin film deposited by sputtering. SOLUTION: The method for recovering high-purity tantalum comprises steps of: dissolving tantalum scrap, such as tantalum chips, by means of hydrofluoric acid or mixed acid of hydrofluoric acid and nitric acid and removing an undissolved residue; adding a potassium-containing salt to precipitate a tantalum fluoride potassium crystal; and further subjecting this tantalum fluoride potassium crystal to sodium reduction to obtain metal tantalum powder.</p> |
