| 摘要 |
According to the present invention, a method for recovering silver and platinum from waste paste using phosphoric acid comprises: (1) a step of manufacturing a mixed solution containing phosphoric acid and hydrogen peroxide; (2) a step of adding waste paste to the mixed solution to dissolve the waste paste to manufacture a silver/platinum-dissolved solution; (3) a step of adding sodium chloride to the silver/platinum-dissolved solution to precipitate silver ions into silver chloride; (4) a step of filtering the precipitated silver chloride to dry the silver chloride, then placing the silver chloride in sulfuric acid, and reducing the silver chloride using zinc to recover silver; (5) a step of adding ammonium chloride to a solution remaining after filtering the silver chloride to precipitate the mixture into chloroplatinic ammonium; and (6) a step of filtering and drying the precipitated chloroplatinic ammonium, and then plasticizing the chloroplatinic ammonium to recover platinum. The method for recovering silver and platinum from waste paste using phosphoric acid in accordance with the present invention uses a mixed solution of phosphoric acid and hydrogen peroxide having an excellent dissolution rate for silver and platinum to efficiently recover silver and platinum from waste paste without using strong acid such as hydrochloric acid, nitric acid, etc. which causes an environmental problem such as emission of toxic gas harmful to the human body. |
