| 摘要 |
<P>PROBLEM TO BE SOLVED: To increase recovery efficiency of noble metals by selectively separating noble metals from dental material-polished powder, and concentrating the noble metals in the refining raw material to increase the grade thereof. <P>SOLUTION: A method for concentrating noble metals in refining raw material containing dental material-polished powder by a floataion process is disclosed which concentrates one or more noble metals selected from the group consisting of Au, Pd and Ag in the refining raw material containing the dental material-polished powder. The method includes: a step (A) where dental material-polished powder is roasted at ≥750°C; a step (B) where the roasted matter obtained in the step (A) is pulverized, water and dilute sulfuric acid are mixed thereto to obtain sulfuric-acid-acidified slurry whose pH is adjusted to pH 1 to 4; and a step (C) where a sulfurizing agent, a xanthate-based scavenger and foaming agent are added to the slurry obtained in the step (B), floatation is performed, a floated product (froth) containing the above noble metal(s) is recovered to be separated from settled product (tailing). <P>COPYRIGHT: (C)2011,JPO&INPIT |
