Natural ore samples experiments
The copper–sulfur and lead–zinc ores were crushed to 2.0 mm before samples were ground to 65.0% passing 0.074 mm in a closed stainless steel XMQ-240 × 90 ball mill at a pulp density of 62.5% by weight. To depress the pyrite and sphalerite,1200 g/t and 6000 g/t lime were put into the mill while grinding and the pulp pH will be adjusted to 8 and 11 respectively.During the flotation the milled ores were transferred into a 3.0 L XFG single-trough flotation cell. The reagents were added into the flotation cell in sequence of collector and frother with a containing time of 2 and 1 min. The time of rough Diffuse reflectance infrared spectroscopy (DIR) was used to characterize the surface species on the mineral particle streated. Samples were ground to be less than 5 m and were prepared the same way used in micro-flotation tests. The spec-trum was obtained with the same instrument and presented without any baseline correction