Abstract
This study investigated the use of coke for the recovery of minerals included in the composition of ferruginous sands of the alumina production from bauxites of Kazakhstan. The granulometric and mineralogical analyses showed that that fine ferruginous sands were enriched with iron oxides (up to 67.8% Fe₂O₃), while the coarse fractions possessed higher alumina concentrations, primarily in gibbsite and kaolinite. The reduction experiments were conducted using ore-coke-lime briquettes, which were prepared from ferruginous sands (0.40 - 0.63 mm fraction), metallurgical coke, lime, and bentonite. The testing of smelting from 1200 - 1450 °C, demonstrated that the metallic iron was completely separated from slag at 1400–1450 °C, obtaining a metallic phase with 92.62% Fe. The coke content influenced the reduction efficiency, with results obtained at up to 20% coke. The product of the metallic phase was analyzed by X-Ray Fluorescence (XRF), confirming the high purity of the metallic product, while the slag phase, rich in Al₂O₃, SiO₂, and CaO, was successfully tested as a filler in concrete production. The analysis of the chemical composition of the resulting slag revealed the possibility of its use as a filler in the production of construction concrete.