Common retarders in mineral processing chemical products

                                                      Common retarders in mineral processing chemical products

The more commonly used retarders in mineral processing reagents are: sodium sulfide, zinc sulfate, sodium nitrate, potassium dichromate, water glass, lime, yellow blood salt, tannin, starch (dextrin), carboxymethyl cellulose, etc.

1. Sodium sulphide

Sodium sulphide is an activator for non-ferrous metal oxide ores, and it is also a type of retarder with a relatively high frequency of use in mineral processing reagents.

Sodium sulfide is made by burning coal, charcoal and other reducing gases to restore sodium sulfate (Na2SO4). Sodium sulfide is used as a retarder for sulfide ores in flotation reagent operations. In the practice of molybdenum selection, sodium sulfide inhibits pyrite, and kerosene is used as a collector to float molybdenite. Because molybdenite has excellent natural floatability and will not be inhibited by sodium sulfide, sodium sulfide inhibits pyrite, and a qualified molybdenum concentrate is obtained after several concentrations.

2. Sodium (potassium) nitrate

This mineral processing agent is mostly used in the flotation process of polymetallic deposits. Sodium nitrate is used to inhibit sulfide minerals such as pyrite, sphalerite and chalcopyrite. The mixed use of sodium nitrate and zinc sulfate has a good inhibitory effect on sphalerite. When the sodium nitrate content is low, pyrite will be inhibited, when the sodium nitrate content is low, sphalerite will be inhibited, and when the sodium nitrate content is high, various copper sulfide ores will be inhibited.

3. Zinc sulfate

Zinc sulfate production is achieved by using zinc waste from metal processing and dilute sulfuric acid. Zinc sulfate is a retarder for sphalerite, and its effect is not obvious when used alone. However, when it is used together with alkali, sodium nitrate and sodium sulfite, the inhibitory effect is stronger, and the higher Ph value of the slurry, the better the inhibitory effect of this mineral processing agent.