| 摘要 |
<p>Metals are recovered from industrial waste contg. oxides of Zn, Fe, Pb and Cu by treating with hot (90-102 degrees C) NH4Cl sepg. the soln. from undissolved iron oxide, adding Zn to the soln. to ppte Cu and Ph, and cooling the soln. to ppte ZnO. The process permits recovery of metals from fly ash and electric furnace flue dust. The ZnO is used in paint pigment and rubber compounding. Compared with prior art processes the present process has a higher ZnO yield, less contamination with other salts e.g. 0.2% chloride and extensive roasting and evapn. steps are eliminated.</p> |
