Recovery of mica minerals from granite waste for energy applications

Biotite mica mineral is a common rock-forming mineral that is generally found in metamorphic rocks, but also in igneous rocks. In addition to their high tensile strength, high thermal stability, layered form, and high resistance to chemical and environmental degradation, mica materials also have high electrical resistance. They possess interesting dielectric properties that make them ideal for a number of applications, particularly as a low-cost substitute material for energy storage systems, due to their exceptional insulating characteristics that allow for the transmission of electrical force without conduction. The aim of this article is to investigate the possibility of recovering biotite from granite waste, as part of a circular economy approach, by using a less polluting technique—that of high-intensity dry magnetic separation. Particle size analysis, inductively coupled plasma spectrometry, and X-ray diffraction were used for physicochemical and structural characterization. The findings of this study reveal promising results in terms of content and yield, underlining the effectiveness of this method for biotite recovery compared with other conventional techniques that are used to obtain a high degree of mica biotite purity, as is required in the field of energy storage. This technique is also useful in terms ofgetting rid of waste that represents a heavy environmental burden and has no economic value.