How to separate copper, iron and zinc from polymetallic ores?

Iron, copper, and zinc are currently the most widely consumed metals in the world, and they are relatively important raw materials for industries such as automobiles, aviation, construction, machinery, and ships. With the continuous development of the national economy, the consumption of copper, zinc and iron ore resources is gradually increasing. Copper, zinc and iron mainly exist in the form of complex polymetallic ores in China.

The common method for separating iron minerals from copper and zinc sulfide minerals is magnetic separation, and flotation is a commonly used method for enriching copper and zinc. Therefore, the combined flotation-magnetic separation process is usually used to separate and enrich copper, zinc and iron from polymetallic ores.

However, it is still difficult to achieve complete separation of copper and zinc by flotation.

The main reasons are as follows:

(a) Copper-zinc minerals are tightly intercalated, and it is difficult to dissociate copper-zinc minerals;

(b) During the grinding process, copper ions in the pulp are adsorbed on the surface of sphalerite, resulting in sphalerite having a floatability similar to that of chalcopyrite;

(c) Copper and zinc sulfide minerals are easily oxidized, resulting in poor floatability.

Therefore we opted for hybrid flotation. After the first grinding, copper sulfide minerals and some zinc sulfide minerals with good floatability are floated at the same time. The mixed concentrate is re-ground, and then the copper and zinc minerals in the mixed concentrate are re-ground and separated, and the zinc minerals with poor flotation performance in the tailings are floated separately. Industrially, the simplicity of the process combined with the selectivity of the collector Z-200 (O-isopropyl-N-ethylthiocarbamate) has facilitated its widespread use.