Abstract: The tailing from the magnetic separation of an Anhui magnetite ore contains copper and sulfur, which is characterized by low copper grade, fine dissemination copper mineral and high slime content. When it is treated by conventional flotation reagents and flowsheet that consists of copper-sulfur bulk flotation, copper separation from sulfur and middling recirculation in sequence, the obtained copper concentrate will have a grade on only 15.62% and a recovery of only 75.38%. Therefore, self-developed ester type sulfide ore collector PL411 is used in the industrial test with a new process of middling selective grinding-flotation closed circuit, finally obtaining a copper concentrate having a grade and recovery of 22.13% and 81.88% respectively and a sulfur concentrate having a grade and recovery of 46.58% and 78.47% respectively. The test results have laid a foundation for the secondary exploitation of the tailing of an Anhui magnetite ore and will also have some reference to the comprehensive utilization of other similar magnetite ores.

Key words: Tailing of magnetic separation, Copper separation, New collector PL 114, Selective grinding and flotation