Production of geopolymer from phosphate ore waste produced in Araxá.
geopolymer, tailings, phosphate mining, acid activation
Brazil is an important global producer of mineral commodities.On the other hand, the impacts of mineral activity cause permanent and non-mitigable damage.The waste generated in the concentration of ore is currently disposed of in dams, geotechnical structures that must be permanently monitored, even after being de-characterized, as they remain storing mining by-products.Geopolymers are cementitious materials with properties similar to those of Portland cement obtained from the reaction of a precursor source and an alkaline or acid activator.Among the various precursors studied, mining tailings have the potential to be used as raw materials to obtain geopolymers.In addition to the availability of this type of material, more noble destinations such as its reuse can help minimize the impact of mining as well as enable more sustainable processes for obtaining cementitious materials with applications in civil construction.In this sense, the waste from phosphate mining, carried out in the municipality of Araxá, was characterized using the methods X-ray Diffraction (XRD), X-ray Fluorescence (XRF), Scanning Electron Microscopy (SEM), Granulometric Analysis and determination ofspecific surface area using the BET method.Based on the results obtained and given the physical-chemical characteristics of the waste, acid activation of the waste was carried out using concentrated H3PO4 (80%).The product obtained presented high porosity, making it impossible to carry out a compression resistance test, however, from the literature review, possible contaminants were identified that could contribute to the presence of pores in the geopolymer obtained, indicating the efforts that must be made in theupcoming study.