A method of comparison of the frothing and collecting properties of frothers

Abstract It is commonly acknowledged that various n-alkanols differ in their flotation properties. Usually, the flotation properties of n-alkanols are estimated by comparing flotation yields at a chosen alcohol concentration. However, the final result of a flotation test depends on the reagent action at liquid/gas, liquid/solid, and solid/gas interfaces. Thus, the comparison and evaluation of flotation collectors and frothers would be more reliable if done in terms of a parameter characterizing surface properties of the system. Frothing properties of solutions were measured by a pneumatic method and described in terms of retention time ( rt ) and dynamic frothability index (DFI) values. DFI characterizes solely the frothing properties of the reagent itself and can thus be considered as a material constant. The product of DFI and the given solution concentration ( c ) gives information about the frothability of the solution. Flotation tests, for coals of ranks 32, 33, and 34 were carried out in a laboratory Denver-type cell. Comparison of the flotation results as a function of DFI. c showed that the flotation yields were not dependent on the kind of n-alkanol used. This means that n-butanol, n-pentanol and n-hexanol showed the same collecting properties.