| 摘要 |
PROBLEM TO BE SOLVED: To obtain a reducing agent for enabling metals containing a noble metal to recover effectively and furthermore, having no adhesion of metals or the like to an inner wall or the like of a reaction vessel by using one selected from hydrazinoalcohols or salts thereof as an active ingredient. SOLUTION: This reducing agent makes at least one selected from hydrazinoalcohols represented by the general formula, HORNHNH2 (wherein R is a 1-8C alkylene group of a straight or branched chain) and salts thereof as an active ingredient. As the reducing agent, particularly 4-hydrazinobutanol, and hydrochloride, sulfate, sulfonate and sulfamate thereof are preferable. The reducing agent can be used for various metals to be recovered by reduction, and to use it for recovering noble metals of gold, silver, palladium, osmium, rhenium or the like is preferable. The reducing agent is preferably used for recovering metals from an aqueous solution. An amount used of the reducing agent is usually at least 1.5 mole, preferably 3-7 mole. per 1 mole of a metal to be recovered.
|
