A Review on the Application of Starch as Depressant in Iron Ore Flotation

The depletion of high-grade iron ores has necessitated the beneficiation of low-grade iron ores. Flotation is considered the most efficient operation to upgrade the iron content of fine-grained ores that do not respond to gravity or size classification units. Out of several reagents used in iron ore reverse flotation, depressants play a crucial role in selectively making the iron oxides hydrophilic and prohibiting them from reporting to the gangue-rich froth phase. Starch is widely used as the depressant in iron ore flotation. The present paper attempts to highlight different facets of starch as an iron ore depressant. It reviews the important research papers that discuss the origin and chemistry of starch, starch-iron oxide interaction mechanism, and the application of different types of starches and their alternatives in iron ore flotation.

Automated summary

The depletion of high-grade iron ores has led to the need for beneficiation of low-grade iron ores. Flotation is considered the most efficient method to increase the iron content of fine-grained ores that do not respond to gravity or size classification. Depressants are crucial in iron ore reverse flotation as they selectively make iron oxides hydrophilic and prevent them from entering the gangue-rich froth phase. Starch is widely used as a depressant in iron ore flotation. This paper reviews the origin and chemistry of starch, the mechanism of starch-iron oxide interaction, and the application of different types of starch and their alternatives in iron ore flotation.