The paper presents the results of experimental research into the recovery of Fe-Al coagulant from iron ore tailings (IOTs). The variables investigated in the laboratory tests included sulphuric acid concentration, temperature, leaching time, solid/liquid phase ratio (S:L) and the presence of stirring. The experiment determined the composition of the coagulant and the solid residue after leaching. The maximum iron content in the solution after leaching was obtained using 40 % H2SO4 at a temperature of 100 °C (or with stirring at 75 °C) and a contact time of 60 minutes. In this case, the iron yield was at the level of 25 % of the total content in the iron ore tailings. Chemical analysis of the solution obtained after leaching showed Fe and Al sulphate contents of 11 and 2 % respectively. In the next step, the efficiency of the coagulant was evaluated on model solutions of colour. The experimental results showed that the coagulant obtained from the iron ore tailings can be used for wastewater treatment in a wide pH range from 4 to 12 pH units. The solid residue after leaching is a fine-grained powder rich in silica, which can potentially be used as an artificial raw material in the construction industry. The research carried out in this thesis has shown that the extraction of coagulants from iron ore tailings can be considered as a way to extend the production chain of iron ore mining and to minimise the amount of tailings to be stored in tailing ponds. The technical solution presented in this work allows to comprehensively solve the problem of environmental protection by creating new target products for wastewater treatment from IOTs.
