Study on inhibition effect and mechanism of sodium humate in hematite reverse flotation

The inhibitor can improve the hydrophilicity of minerals and prevent minerals from interacting with collectors. It plays an important role in the reverse cation flotation of iron ore, and it has become the focus of current research to find efficient, environmental friendly and cheap inhibitors. Sodium humate (NaHA) is a product extracted from weathered Lignite by means of biodegradation and organic decomposition. In this study, this new inhibitor NaHA was used to separate hematite and quartz. The results of micro-flotation showed that an appropriate concentration of NaHA could selectively inhibit hematite and realize the effective separation of quartz and hematite. Zeta potential and adsorption measurement results showed that after treatment by NaHA, the negative shift of zeta potential of hematite was more obvious, and could prevent the further adsorption of dodecylamine (DDA). The adsorption capacity of NaHA on hematite surface was much greater than that on quartz surface. FTIR results showed that there was chemisorption of NaHA on the surface of hematite but no on the quartz. XPS analysis again confirmed that NaHA may adsorb on the surface of hematite through coordination with surface iron.