| 摘要 |
<p>Ores in which at least a portion of the floatable material is present as an oxygen-containing compound and which contain siliceous gangue are concentrated by a froth flotation process in which a higher fatty acid or a salt of such an acid is used as collecting agent and a soluble cyanide is added as a depressing agent for the gangue. The fatty acid must contain at least 8 carbon atoms in the molecule, oleic acid, sodium oleate, stearic acid, and stearates being specifically referred to. Other collecting agents such as xanthates and frothers such as pine oil may be added. The cyanide also improves the quality of the froth and in some cases acts as an activator for the oxidized mineral. The flotation of oxidized and mixed sulphide-oxide copper ores and of non-metallic minerals, e.g. kyanite, is referred to. The use of sodium silicate, sodium carbonate, and gums as depressing agents for silica &c. also is referred to.</p> |
