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Based on geological, mineralogical, physical, chemical and technological investigations in the Tamnava Tertiary Basin near Sabac town (western Serbia), deposits of ceramic clays were studied. These ceramic clays are composed of kaolin-illite with a variable content of quartz, feldspars, mica, iron oxides and hydroxides, and organic matter. Four main types of commercial clays were identified: i) red-yellow sandy-gravely (brick clays); ii) grey-white poor sandy (ceramic clays); iii) dark-carbonaceous (ceramic clays); and iv) lamellar (?interspersed?) fatty, poor sandy (highly aluminous and ferrous clays). Ceramic clays are defined as medium to high plastic with different ranges of sintering temperatures, which makes them suitable for the production of various kinds of materials in the ceramic industry. [Projekat Ministarstva nauke Republike Srbije, br. OI-176016]

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The investigation results of the processing possibilities of the complex barite‐sulphide ore from “Bobija” deposit (Serbia) for the sake of lead, zinc and copper extraction are presented in this paper. Through x‐ray diffraction and microscopic examination it is concluded that: (a) it is not possible to enrich the ore for obtaining any selective or a collective sulphide concentrate using the conventional methods of mineral processing, and (b) it is necessary to include chemical and technological procedures for ore processing. Examination of reduction roasting with carbon addition for the barite (BaSO4) reduction into good soluble BaS is performed. After water leaching of BaS from the calcined ore, the solid residual is submitted to the magnetic separation procedure for the pyrrhotite (Fex−1Sx) separation, which is formed after pyrite (FeS2) dissociation, and for obtaining a collective sulphide concentrate Pb–Zn–Cu. Finally, the sulphide concentrate is leached with the solution of H2SO4 in the presence of oxygen at elevated temperatures and pressures in an autoclave. Through their sulphide oxidation zinc, copper and iron were dissolved, while lead sulphide remained as insoluble in the solid residual after leaching. The influence of the working parameters on the degree of leaching of zinc, copper and iron is examined.

During the production of steel by a converter process, a slag is produced and stored at slag depots, thus causing serious difficulties through pollution and space requirements. A converter slag is a compact and abrasive raw material containing CaO and Fe. The investigations showed that a multi-stage crushing, classifying and magnetic separation operations influence successful steel recovering from slag, while slag itself is converted into a high-grade fluxing agent which can be used in production of sinter and raw iron. Also, positive economic effects are achieved through a partial substitution of more expensive limestone and a full substitution of Mn---ore and dolomite.