In this study, we investigate the reduction smelting of antimony concentrate, where sodium antimonate is the primary antimony-bearing component, in alkaline melts. This study aims to reduce the carbon footprint of metallic antimony production. It is shown that traditional carbon reduction is accompanied by significant formation of carbon-containing gases and sodium losses due to volatilization. Based on thermodynamic analysis and experimental investigations, carbon monoxide is established as the key active gaseous reducing agent for antimonate compounds, predominantly operating in the temperature range of approximately 320–900 °C, which corresponds to the stages of coke oxidation and sodium antimonate decomposition. The authors propose introducing sodium hydroxide into the charge to form an alkaline melt with a lowered melting point when mixed with the antimony concentrate, ensuring the sequestration of carbon dioxide through the formation of sodium carbonate. Experiments confirmed the possibility of chemically fixing up to 75.5% of CO2 into the slag phase at the laboratory stage and up to 87% of CO2 during pilot tests of reduction smelting under a flux layer. Crude metal with an antimony content of 94–96.2% Sb was obtained, while coke consumption was reduced by 16–20%. The proposed approach ensures a simultaneous increase in the degree of antimony recovery, the utilization of carbon-containing gases, and the formation of a stable eutectic slag melt. This allows the process to be considered an element of carbon-neutral pyrometallurgical technology for processing antimony concentrates.
The article presents the results of oxidative leaching of lead sludge from copper production in order to extract rhenium into solution. The optimum regimes for product leaching man-made product in the presence of sodium peroxocarbonate Na2CO31.5H2O2 has been established: Experimental work was carried out under the following conditions: oxidant consumption 5 by weight of the raw material, leaching temperature 70C, duration 3060minutes, stirring speed 200rpm, and the ratio of liquid to solid S:L=1:3. The degree of extraction of rhenium into the solution is 9597, and the content reaches 500520mg/L Re.
10 October 2025 in Kompleksnoe Ispolzovanie Mineralnogo Syra = Complex Use of Mineral Resources
The increasing demand for non-ferrous, precious, and rare metals necessitates more comprehensive and efficient use of mineral raw materials, such as gold-antimony ores and concentrates. A promising approach is the use of pyrometallurgical processing in a fluidized bed, which offers more efficient heat and mass transfer than conventional technologies. This study aims to investigate the evaporation kinetics of antimony sulfide (Sb2S3) from gold-antimony ores and concentrates in a fluidized bed under various conditions. The experiments involved varying temperature (923-1223 K), particle size (0.09-2.0 mm), and layer thickness (5-15 mm) to determine the evaporation rate of Sb2S3. The experimental setup consisted of a laboratory-scale fluidized bed reactor equipped with a controlled gas flow of nitrogen mixed with sulfur vapor. The evaporation rates were measured using a gravimetric method and confirmed by X-ray diffraction and microscopic analysis of samples. The results show that the evaporation rate of Sb2S3 in a fluidized bed is 7-9 times higher than in a fixed bed. This is due to significantly improved heat and mass transfer in the fluidized system. At 1023 K, the overall evaporation rate increased with decreasing grain size. This is associated with an increase in the total surface area of the material, but the specific evaporation rate normalized to unit surface area was independent of particle size. The process was not significantly affected by bed height in the range of 5-15 mm. Antimony recovery into sublimates improved by 2-3% compared to conventional technology. It reached 98-99% due to suppression of Sb2O5 formation. These findings confirm the efficiency of supplying an inert gas with sulfur vapors into the fluidized bed. This reduces harmful gas emissions and minimizes dust entrainment. It also allows for effective distillation of volatile components at lower temperatures.