| Abstract [eng] |
The aim of this research was to evaluate the feasibility of utilizing waste material, that is produced during MgSO4 synthesis from serpentinite, in cement systems. Analytical tests revealed that the waste contains oxides commonly found in conventional cement components. In order to minimise the chemical composition adjustment of the waste, brownmillerite and akermanite minerals were synthesised. To achieve the stoichiometric ratios necessary for the synthesis of brownmillerite CaO : Al2O3 : Fe2 O3 (4 : 1 : 1) and akermanite CaO : MgO : SiO2 (2 : 1 : 2), the waste composition was modified through the addition of chemical reagents. To assess the impact of soluble sulphates present in the waste on material synthesis, experiments were conducted using both washed and unwashed waste samples. In the case of brownmillerite, no formation was observed post-synthesis. However, akermanite was successfully synthesized under similar conditions. To determine the potential application of these materials in cement systems, hydration and geopolymerisation properties were analysed, products were prepared and tested for compressive strength after 7 and 28 days of hardening. The results provided insights into the mechanical performance and viability of integrating modified waste into cementitious compositions. |
