Metal borides and carbides, TiB2/TiC and ZrB2/ZrC are widely used nanostructured composite materials. A detailed thermodynamic analysis was performed to determine the formation conditions of titanium and zirconium borides and carbides in the Ti-B-O-C and Zr-B-O-C systems. The complete thermodynamic analysis was carried out in vacuum for the reactions 2TiO2 + B2O3 + 8C = TiB2 + TiC + 7CO and 2ZrO2 + B2O3 + 8C = ZrB2 + ZrC + 7СО. On the basis of the theoretically found results, experimental synthetic routes were developed to prepare TiB2/TiC and ZrB2/ZrC composite materials.

Abstract:A new technology for integrated processing of gold-bearing antimony ores has been developed in order to solve certain problems in the gold-mining industry. The technology based on vacuum-thermal processes allows not only extraction of gold but also production of associated materials-antimony sulfide (Sb 2 S 3 ) and metallic antimony (Sb). The paper presents theoretical as well as applied research. Kinetics of the process of antimony sulfide extraction from the ores was studied for different fractions. Optimal conditions for obtaining of Sb 2 S 3 were determined. The resulting product was a high-purity metallic Sb (~99.2 mass%). For extraction of gold from a cinder of vacuum-thermal processing of a concentrate, along with a thiourea method, the ecologically pure electrochemical method of our elaboration has been used. The effect of main technological parameters on the process of electrochemical leaching of the residues has been studied in the presence of gold complex former-thiourea in chloride system and optimal conditions of leaching were established providing the gold extraction from gold-containing residues by 82-90% in the conditions of so-called "soft" oxidation without release of molecular chlorine at the anode and eco-contamination.