The influence of roasting temperature on the flotation properties of muscovite

Abstract

Roasting and flotation are common techniques used in mineral processing, and they have increasingly been combined for the pre-concentration of muscovite from stone coal. The research was mainly to study flotation properties of muscovite after roasting at 200, 400, 600, 800 and 1000 ˝C, respectively. The changes of chemical and physical properties of muscovite during the roasting process were investigated by thermogravimetric analysis (TGA), Fourier transform infrared spectrum (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Zeta potential measurements, particle size analysis, and the BET surface area measurements. The results indicated that the dehydroxylation of crystal structure took place at temperatures over 600 ˚C. A large number of hydroxyl groups were removed from the crystal structure of muscovite at 600-1000 ˚C. The layer structure, surface element distribution, and electrical properties of muscovite remained after roasting. The flotation recovery of roasted muscovite samples increased with the increase in roasting temperature in the same flotation system, because the specific surface and the adsorption capacity of dodecylamine (DDA) were reduced when roasting temperature was over 600 ˝C. A suitable roasting temperature and dosage of reagents can be provided for the roasting-flotation of muscovite.