Technical challenges in the flotation of molybdenite from porphyry copper ores

Molybdenite is a valuable by-product in copper flotation. Driven by economic considerations, the recovery of molybdenite from low-grade porphyry copper ores has become of great interest in the last decade. In typical bulk copper/molybdenum flotation circuits, the copper sulfide minerals generally show higher and more stable flotation rate and recovery, while molybdenite recovery is highly variable and sensitive to the operating conditions. As a result, significant molybdenite losses may occur. The performance of different concentrators treating porphyry copper ore has been investigated within the AMIRA P260E project, revealing common issues related to molybdenite recovery. An overview of the major findings is given, and mechanisms and factors affecting molybdenite flotation are discussed. Technical challenges are presented and solutions to ensure higher and more stable molybdenite recovery suggested.M. Zanin, S. Grano and I. Ameto