[en] Present article is devoted to sulfuric acid decomposition of argillite and kaolin clays of Zidda and Chashma-Sang Deposits of Tajikistan. The thermolysis processes of initial and calcined argillite was studied at 100-1000 deg C temperature range. The influence of temperature, process duration and concentration of sulfuric acid on extraction rate of aluminium and iron oxides from calcined ores was studied as well. The optimal conditions of sulfuric acid decomposition of argillite and kaolin clays of Zidda and Chashma-Sang Deposits of Tajikistan, including temperature, process duration, sulfuric acid concentration and particle size were proposed.

[en] The decomposition process of argillite by nitric acid was studied. The optimal parameters of argillite decomposition are found. The flowsheet of argillite processing by means of nitric acid decomposition method is proposed. The chemical composition of argillite of Ziddi deposit is presented.

[en] Present article is devoted to acid decomposition of argillite and kaolin clays of Chashma-Sang Deposit of Tajikistan. The conditions of decomposition of argillite and kaolin clays by sulfuric acid with yield of aluminium and iron sulphates which could be used as coagulants for purification of drinking water were studied. The dependence of extraction rate of aluminium and iron oxides from the calcined ores on temperature, process duration, sulfuric acid concentration was defined. The optimal conditions of acid decomposition of argillite and kaolin clays were found and proposed.

[en] This article is devoted to processing of kaolin clays by nitric acid with obtaining of aluminium nitrates and iron which can be used as a raw materials for obtaining of chemical fertilizers. The spectral analysis of initial kaolin clay by means of atomic emission spectral analysis method is conducted. The results are presented. The influence of temperature, process duration and acid concentration on the rate of minerals extraction is studied in this work as well.

[en] The kinetics of hydrochloride-acid decomposition of argillite of Chashma-Sang deposit is studied in this work. The numerical values of activation energy (for Al₂O₃ - 41.32 kj/mol) and dependence of decomposition rate certify that process flows in mixed area, close to kinetic, and for Fe₂O₃ (21.33 kj/mol) - in diffusion area. (author)

[en] Present article is devoted to hydrochloric acid decomposition of kaolin clays of Chashma-Sang Deposit of the Republic of Tajikistan. The spectral analysis of kaolin clay of Chashma-Sang Deposit was conducted. The dependence of extraction rate of Al₂O₃ and Fe₂O₃ on temperature, process duration, and hydrochloric acid concentration was studied. The influence of concentration of hydrochloric acid on ore decomposition was studied as well. The optimal conditions of decomposition of kaolin clay of Chashma-Sang Deposit were proposed.

[en] Kinetics of hydrochloric acid decomposition of kaolin clays of Chashma-Sang Deposit of Tajikistan has been studied. The numerical value of activation energy has been determined, which was for Fe_O3 in the area of 20-40 deg C 33.56 kJ/mol and in the area of 60-98 deg C 17.14 kJ/mol which indicates that process occurs at 20-40 deg C in a mixed area and at 60-98 deg C in a diffusion area. The activation energy of decomposition process of kaolin clay by hydrochloric acid has been defined.