An investigation of froth stability in reverse flotation of collophane

In flotation, froth stability strongly influences the separation process, as such stability is linked to the particle size, mineral content and water quality. In this study, the froth stability in the reverse flotation of collophane was investigated by froth stability tests and froth drainage experiments with the cationic surfactant N1-(3-((8-MethylnonyDoxy)propyl)propane-1,3-diamine (MOPPD). The results indicated that the presence of fine fractions lead to the high froth stability, and the froth stability increased with increases in the mineral content. Furthermore, it was shown that the presence of calcite and dolomite greatly increased the froth stability compared to quartz and fluorapatite. In addition, Ca2+ and Mg2+ dissolved by calcite and dolomite were proved to stabilize the froth structure. On the basis of the froth stability in the reverse flotation of collophane, a strategy for controlling the froth stability through desliming by sedimentation and flotation before quartz removal was proposed. Flotation tests showed that the concentrate grade increased to 28.06% and the froth volume of tailings greatly decreased to 920 mL compared with the values of 24.13% and 4200 mL, respectively, for direct flotation. Overall, the results confirmed that the proposed strategy is crucial for managing froth during quartz removal from collophane.