| 摘要 |
<p>Cassiterite ore is beneficiated by subjecting an aqueous pulp of the ore to froth flotation in the presence of a collector selected from the class consisting of water dispersable alkyl sulphosuccinates and alkyl sulphosuccinamates. The number of carbon atoms in the collector molecule is at least 8 and preferably 18. A particular collector may be dioctyl sulphosuccinate or N- octadecyl tetrasodium 1,2 dicarboxyethyl sulphosuccinamate or may be in the form of another alkali metal salt or of an alkaline earth metal salt. The collector concentration may be between 10-6 and 10-4 mols per litre of pulp. Flotation may be carried out at a pH of between 2.0 and 10.0 The flotation may take place first in rougher cells followed by one or more cleanings of the rougher concentrate. The collector may be added once at the beginning of the operation or in stages. The pulp may contain between 15 and 30% of solids by weight. A frother may be added during the process. Activators for the cassiterite may be added in the form of ions of polyvalent metals, e.g. soluble salts of ferric iron, lead, zinc or copper in amounts not exceeding 10-2 mols per litre. Small amounts of a sulphide collector, e.g. a xanthate, may be added at the same time. When the ore contains minerals such as tourmaline, topaz, fluorite, siderite and iron oxides, e.g. hematite or magnetite, these may be depressed by the addition of small amounts of soluble silicates, fluosilicates, ferrocyamides or ferricyamides either at the roughing or cleaning stage. Sulphide flotation reagents may be used to remove sulphide minerals, if present, before flotation of the cassiterite.</p> |
