Dataset on eco-friendly cement production using iron ore tailings from Brazil and evaluation of grinding process on the synthesis of geopolymers

The use of iron ore tailings in Brazil is an important topic after two recent tragedies. The data was collected in order to understand the geomechanical feasibility of eco-friendly cements using iron ore tailings and evaluate the impact of the grinding process on the compressive strength of geopolymers. The data is based on two major studies using the same methodology. The first one is the examination of the material best composition in terms of uniaxial compression resistance by varying its proportions of iron ore tailings, metakaolin and alkaline solution (composed by 1:3 ratio of sodium hydroxide (NaOH) and sodium silicate (Na2SiO3)). The second one is the evaluation of the effects in compressive strength when grinding the iron ore tailings for 1, 2 and 3 hours for producing the geopolymer. The best proportion consisted in 50% of iron ore tailings, 25% of metakaolin and 25% of a alkaline solution obtained an uniaxial compressive strength resistance of 23.5 MPa in 3 days. Also, the gain obtained with the ground tailings after 3 hours only occurs in the firsts days of cure, which does not justify grinding for this iron ore tailings due to the high cost of this operation. Tests with 1 and 2 hours of tailings grinding showed lower results of UCS when compared with IOT without milling, which is unexpected and needs further investigation to understand this behavior. One possible explanation is material agglomeration during the initial grinding times, and it is feasible that the clustering of particles limited the reaction. Finally, it appears that geopolymer mortars seem to be a viable alternative for the sustainable use of IOT in the state of Minas Gerais, in Brazil, since they present satisfactory results of compressive strength