The effects of increasing ionic strength, collector chain length, and temperature on the anionic flotation of oxide minerals

Abstract

The effect of increasing ionic strength on the flotation characteristics of hematite and silica has been investigated. Alkyl sulfate collector chain length and pretreatment temperature were critical parameters related to the varying ionic strength. Sodium hexadecyl sulfate was shown to be a superior flotation collector to sodium dodecyl sulfate for recovery of hematite with no salt addition. Similar observations were made when sodium sulfate or sodium chloride was used to control ionic strength. Sodium dodecyl sulfate floated hematite and silica better than its longer chained counterpart under conditions of low pretreatment temperature and increasing calcium chloride concentration. The flotation recovery for all salt containing pulps was almost always improved after preboiling.