The chemical name of the black drug is alkyl dithiophosphate. The commonly used is a benzoyl black, which is divided into dithiophosphate 15, dithiophosphate 25 and dithiophosphate 31 because of the amount of phosphorus added to the production of the ingredients. In recent years, successful butylammonium black drugs have been successfully tested.
The black drug is used in the flotation of pyrite, lead and zinc polymetallic ores.
Black powder is characterized by: dark green oily liquid, corrosive, slightly soluble in water, decomposition, except there are collecting performance and foaming properties, its good selectivity and collecting ability of pyrite is poorer. It should be pointed out that the black drug is not easy to decompose in acidic pulp, and it is also difficult to oxidize. However, due to a small amount of H2SNa2S and other revulcanization agents, it is appropriate to select the sulfide ore which is slightly oxidized with black.