| 摘要 |
<p>311,369. Zaklady Hohenlohego-Hohenlohe-Werke Spolka Akcyjna. May 10, 1928, [Convention date]. Void [Published under Sect. 91 of the Acts]. Zinc and lead sulphates.-Zinc containing materials such as roasted zinc ores or mixed zinc and lead oxides are heated with liquid sulphuric acid at a temperature of about 400' C. and then leached to obtain a zinc sulphate solution and, when lead is present, a residue of lead sulphate. Excess of dilute acid of Sp. Gr. 1.5 is used and the heating may take place in a superposed hearth furnace. The products are free from chlorine.</p> |
