Circular 53—Froth flotation of ion-exchange resins and its applications

By R. B. Bhappu, 1961, 23 pp., 5 tables, 2 figs.

Efforts of froth-float ion-exchange resins from unclarified liquors and pulps containing a high percentage of solids have resulted in the development of effective procedures for floating such resins. Cation-exchange resins are collected and floated with cationic amine-type collectors, whereas anion-exchange resins are amenable to flotation with collectors of the anionic sulfonate and thiophosphate types. The results of preliminary tests of the resin-flotation technique in the hydrometallurgical treatment of natural ores of copper, uranium, and gold have demonstrated the technical and economic feasibility of such a process.

With the ever-increasing demand for today's metals and for others whose uses are only now being explored, it is inevitable that wet-process metallurgy will be increasingly employed in metals production. Even in the case of metals that have been in use for hundreds of years, the increased recoveries now required, which spell the margin between profit and loss, and the more complex and poorer grades of ore that must be worked, can only mean that new hydrometallurgical processes must be developed and existing processes improved.

One newly developed technique, whose potentialities in hydrometallurgy have only recently been recognized, is ion exchange. This age-old process is finding new uses in many fields of endeavor because it is often uniquely suited where conventional techniques fail. Ion-exchange processes are flexible, and the necessary equipment can be designed for a minimum of operating attention. Generally speaking, there are three areas in which ion exchange can be profitably employed in hydrometallurgical practice: (1) where metals are being recovered by less economical methods; (2) where metals are being lost; and (3) where recovery of metals is otherwise economically impractical. These areas immediately suggest several applications of ion-exchange techniques in the mining and metallurgical industry. Some of these have been successfully used in practice for years, whereas others are in the development or pilot-plant stage.