THE EFFECT OF NONIONIC REAGENT ADSORPTION AND FLOTATION PERFORMANCE OF 2 LOW-RANK BRITISH COALS

In the froth flotation of ultra-fine particles, the recovery and purit y of the final product obtained depend largely on the froth structure, which in turn is affected by reagent adsorption on the solids. In thi s study, ultra-fine particles (5 mu m size fractions) of two low rank British coals were used in the flotation tests. The tests were carried out using only one of two different non-ionic reagents; diacetone alc ohol and 2-ethyl hexanol. The froth structure can be changed significa ntly by addition of reagent. It was observed that when the froth struc ture changes from a spherical to a polyhedral structure that the flota tion performance changes significantly. Previous measurements of the i nternal pore distributions showed marked differences between the Rawdo n and Bickershaw coals. Also the flotation performance of each coal di ffered significantly according to the reagent used. It is postulated t hat the differing behaviour of the coals can be attributed to the frac tional amount of the total reagent adsorbed on the interior pore surfa ces.