How do biopolymer depressants work in mineral processing?

The use of biopolymers may improve the recovery and quality of valuable metals by enhancing the effectiveness of the collectors.

Biopolymer depressants are added to the froth flotation process in order to maintain or create hydrophilic surfaces on minerals. This helps to keep the minerals in the pulp, rather than allowing them to float with the froth. These biopolymers have the ability to selectively depress gangue materials, such as pyrite, clay, and talc, by dispersing them. They primarily adsorb onto gangue minerals, rather than valuable minerals.

Once they are adsorbed, the biopolymers prevent the collector from adsorbing onto the gangue minerals and also reduce the strength of the galvanic interactions between sulfide minerals. The adsorbed layer of biopolymer enhances the hydrophilic nature of the gangue surfaces.

In essence, the use of biopolymers may improve the recovery and quality of valuable metals by enhancing the effectiveness of the collectors.