| 摘要 |
The present invention provides a method to recover silver from waste silver paste using malonic acid, comprising: (a) a step of forming mixed solution including malonic acid and hydrogen peroxide; (b) a step of forming silver dissolved solution by injecting silver paste to the mixed solution to be dissolved; (c) a step of putting sodium chloride (NaCl) into the dissolved silver solution to allow silver ions to be precipitated into silver chloride (AgCl); (d) a step of filtering the precipitated silver chloride to be dried; (e) a step of recovering silver by reducing the dried silver chloride; and (f) a step of melting the recovered gray silver at high temperature and cooling the silver to be manufactured as silver bullions with a silver-white color. The method to recover silver from waste silver paste using malonic acid is able to solve environmental problems such as the dischargement of gas harmful to the human body or water pollution due to a usage of inorganic acid using organic acid and hydrogen peroxide, and efficiently recover silver from silver paste using malonic acid with a high rate of dissolving silver. |
