摘要 |
<p>1,181,418. Froth flotation. D WESTON. 13 Nov., 1967 [28 Nov., 1966], No. 51604/67. Heading B2H. In a process for floating a phosphate, a carbonate or silica or a mixture of two or more of these minerals in the presence of slimes while metallic oxides are depressed, a suitable pulp of the mineral or mixture is conditioned at a pH of 11-12 in the presence of a dispersing agent comprising sodium silicate and a collecting agent, and the pH is then adjusted to the optimum pH range for mineral flotation in one or more stages. The optimum pH range for silica is 11.0-12.0 whereas that for phosphates and carbonates is 9.5-10.5. Collecting agents mentioned are fatty acid, petroleum sulphonate, and tall oil or a mixture of fatty acid and petroleum sulphonate with or without fuel oil. Sodium silicate is used as dispersing agent. The pH may be adjusted by means of sulphuric acid and sodium hydroxide. Gum may be used as a depressing agent and methyl isobutyl carbinol as a frother. Examples of the treatment of niobium and iron ores are given.</p> |