| 摘要 |
<p>1,242,188. Recovery of lead. ELECTROLYTIC ZINC CO. OF AUSTRALASIA Ltd. 18 July, 1969 [25 July, 1968], No. 36239/69. Heading C1A. Lead values are recovered from lead bearing material by leaching the material at ambient temperature for not more than 1 hour, with a mixture of ammonium sulphate and aqueous ammonia to produce a supersaturated solution, separating undissolved substances and heating the resulting solution without substantial loss of ammonia to cause lead salt precipitation and separating the precipitated solids and liquor. The lead in the starting lead bearing material is present as the oxide, sulphate or basic sulphate or in a form that can be converted to such compounds. Seed crystals of lead ammonium sulphate or mono basic lead sulphate may be added to the solution before heating. The lead is precipitated from the solution in the form of lead ammonium sulphate, monobasic lead sulphate or a mixture of these two compounds, from which metallic lead can be obtained by conventional processes.</p> |
