Potential recovery of industrial minerals from granite waste as a circular economic opportunity to mitigate its impacts: an evaluative review

Abstract

Granite activity has a major contribution to the over-exploitation of natural resources, causing negative repercussions engendering imbalanced ecosystem. In response to growing demand, there is an urgent need to optimise not only granite industry operations but also related activities such as waste management in order to improve sustainability and strengthen the transition to a circular economy. The feldspar and biotite recovering, from the granite industry, offers an eco-friendly and economically solution typically involves lower operating costs for mitigating both resources-depletion and waste impacts. As technology continues to advance, biotite and feldspar will play an increasingly important role in various sectors, including energy, construction, and industrial applications. Ongoing studies aim improving the performance and sustainability of separation methods to obtain high-quality feldspars with low iron impurities. Besides flotation, gravity separation and leaching, magnetic separation remains an effective and eco-friendly method for extracting iron oxides imparting the ceramic quality, based on the selective adsorption of magnetic particles. Its application, in dry or wet mode, depends on various factors such as chemical and mineralogical composition, grain size, and environmental constraints. The dry mode is often preferred for practical and ecological reasons, for producing high-grade concentrates materials for ceramic and others applications. Although, simultaneous recovery of both minerals is not discussed, literature provides physicochemical criteria influencing their response to separation techniques.