| abstract |
According to the present invention, ruthenium or a ruthenium compound, which is expensive, can be collected with high efficiency even from an aqueous solution containing a water-soluble salt, a lower alcohol, an organic acid or the like, by adding at least one specific inorganic adsorbent to an aqueous solution containing ruthenium or the ruthenium compound, dissolving the entirety or a part of the inorganic adsorbent under an acidic condition, and then adding an alkali to adjust the solution to be an alkaline solution having a pH value of 7 or higher, thereby depositing the inorganic adsorbent while causing the inorganic adsorbent to adsorb ruthenium or the ruthenium compound. |