Sodium sulfide is a commonly used agent in the flotation of sulfide ore. Its main functions are as follows:

1. Sodium sulfide is an inhibitor of most sulfide minerals

When used in large quantities, it can inhibit most sulfide minerals.The descending order in which it inhibits sulfide ore is roughly: galena, sphalerite, chalcopyrite, spotted copper ore, copper blue, pyrite, and brilliant copper ore.Because the natural floatability of Hui molybdenum ore is very good, sodium sulfide cannot inhibit it.Using this, when flotation of Hui molybdenum ore, Na2S can be used to inhibit other sulfide ore.

2. Sodium sulfide is a vulcanizing agent for oxidized ore of non-ferrous metals

The oxidized ore of non-ferrous metals cannot be directly collected by Huangyao.However, if sodium sulfide and non-ferrous metal oxidized ore are added before flotation with Huangyao, a film of sulfide ore can be produced on the surface of the mineral, and Huangyao can capture it.This effect of sodium sulfide is called vulcanization, so it can be used as a vulcanizing agent for oxidized ore of non-ferrous metals.

After the white lead ore is combined with sodium sulfide, the surface color changes from white to dark.After malachite and sodium sulfide act, the surface color changes from green to black, indicating that after vulcanization, the surface of these two minerals produces a sulfide film different from the mineral.

3. Sodium sulfide is a desulfurization agent for mixed concentrates of sulfide ore

When the amount of sodium sulfide is large, it can be used as a yellow medicine collector that adsorbs on the surface of minerals.Therefore, sodium sulfide can be used as a desulfurization agent before the separation of mixed concentrates.For example, before sorting lead-zinc mixed concentrate or copper-lead mixed concentrate, the slurry can be concentrated, a large amount of sodium sulfide can be added to remove the drug, then washed, and fresh water can be added again to adjust the slurry for separation and flotation.

In addition to the above three main effects, because sodium sulfide can precipitate insoluble sulfides with many metal ions, sodium sulfide also has the effect of eliminating certain ions in the slurry that are harmful to flotation.