An Investigation into the Effects of Grinding Medium on Interface Characteristics and Flotation Performance of Sphalerite in Cyanide System

Abstract

The strong contamination of the interface is the main problem that results in low flotation efficiency of sphalerite in cyanide tailings. However, the consumption of cyanide and dissolved oxygen, as well as the concentration of ions including Zn2+ and SCN− in the leaching solution, decreased with the use of ceramic ball medium. The conclusions obtained from SEM–EDS indicated that the use of ceramic ball medium avoided the excessive surface oxidation caused by the galvanic couple actions between the iron ball medium and the sphalerite. XPS analysis also proved that the chemical environment on the surface of sphalerite was optimized by porcelain ball medium compared with iron ball medium, avoiding the formation of Fe–OOH and Fe–O hydrophilic substances, especially [Fe(CN)6]3−, thus increasing the adsorption of the collector on the surface of sphalerite. Therefore, grinding with ceramic ball medium exhibited excellent performance in terms of the cyanide process, which was approximately 5–10% higher than that obtained by grinding with iron ball media in the flotation test.

Keywords

• sphalerite
• grinding media
• cyanidation
• surface properties
• flotation