Mechanism and leaching kinetics of molybdenite concentrate in a hydrogen peroxide-acid system

• Autorzy: Aracena Alvaro , Azocar Alan , Ibáñez Juan Patricio , Jerez Oscar

Identyfikatory

DOI

10.5277/ppmp18139

• Języki publikacji: EN

Abstrakty

EN

The mechanism and leaching kinetics of a molybdenite concentrate in a H2O2-H2SO4 system were studied. The experimental work was performed in a batch reactor equipped with a condenser, a mechanical agitator and a temperature control system. The effects of the temperature, H2O2 and H2SO4 concentrations, particle size, liquid/solid ratio and agitation speed on the Mo recovery were investigated. The thermodynamic results showed that the leaching mechanism it was governed by several intermediate reactions; however, the influences of sulfuric acid and passivation were not observed in the reaction. The most predominant experimental result was the maximum Mo recovery of 81.3% by leaching 64 μm particles at 333 K (60 °C) for 5400 s (90 min). The molybdenum recovery was generally enhanced by increasing the H2O2 and H2SO4 concentrations. However, at H2SO4 concentrations higher than 1.0 mol/dm3, the Mo recovery decreased. Although the agitation speed affected the Mo recovery considerably, high recoveries could be still obtained without mixing. The experimental results and XRD analysis confirmed the reaction mechanisms. The leaching kinetics were analyzed using a shrinking core model in which the rate was controlled by diffusion through a porous layer with radius ro. The reaction rate orders were 1.0 and 0.2 for the H2O2 and H2SO4 concentrations, respectively, and the rate was inversely proportional to the square of the initial particle radius. The calculated activation energy was 75.2 kJ/mol in the temperature range of 278-333 K (5-60 °C).

Słowa kluczowe

EN

molybdenite concentrate; hydrogen peroxide; kinetics; mechanism of reaction

• Wydawca: Oficyna Wydawnicza Politechniki Wrocławskiej
• Czasopismo: Physicochemical Problems of Mineral Processing
• Rocznik: 2019
• Tom: Vol. 55, iss. 1
• Strony: 140--152
• Opis fizyczny: Bibliogr. 9 poz., rys., tab.

Twórcy

autor

Aracena Alvaro

• Escuela de Ingeniería Química, Pontificia Universidad Católica de Valparaíso, Avenida Brasil 2162, Cod. Postal 2362854, Valparaíso, Chile

autor

Azocar Alan

• Departamento de Ingeniería Metalúrgica y de Materiales, Universidad Técnica Federico Santa María, Avenida España 1680, Valparaíso, Chile

autor

Ibáñez Juan Patricio

• Departamento de Ingeniería Metalúrgica y de Materiales, Universidad Técnica Federico Santa María, Avenida España 1680, Valparaíso, Chile

autor

Jerez Oscar

• Instituto de Geología Económica Aplicada (GEA), Universidad de Concepción, Casilla 160-C, Concepción, Chile

Bibliografia

• AGACAYAK T., ARAS A., AYDOGAN S. and ERDEMOGLU M., 2014. Leaching of chalcopyrite concentrate in hydrogen peroxide solution. Physicochemical problems of mineral processing 2. 657-666
• ANTONIJEVIC MM., DIMITRIJEVIC M. and JANKOVIC Z., 1997. Leaching of pyrite with hydrogen peroxide in sulphuric acid. Hydrometallurgy 46. 71-83
• CAO ZF., ZHONG H., QIU Z., LIU G. and ZHANG W., 2009. A novel technology for molybdenum extraction from molybdenite concentrate. Hydrometallurgy 99. 2-6
• GOODARZI M., REZAI B. and SEIFIKHANI A., 2017. Leaching and kinetic modelling of molybdenite concentrate using hydrogen peroxide in sulfuric acid solution. Iran. J. Chem. Chem. Eng. 33. 73-85
• GUPTA CK. 2000. Extractive metallurgy of molybdenum, 1st ed. Florida: CRC Press
• LASHEEN TA., EL-AHMADY ME., HASSIB HB. and HELAL AS., 2013. Oxidative leaching kinetics of molybdenum-uranium ore in H2SO4 using H2O2 as an oxidizing agent. Frontiers of Chemical Science and Engineering 7. 95-102
• MADEJA AS., 2011. Kinetics of Mo, Ni, V and Al leaching from a spent hydrodesulphurization catalyst in a solution containing oxalic acid and hydrogen peroxide. J. Hazard Mater. 186. 2157-2161
• ROINE A., 1999. HSC Chemistry 6.0. Pori, Finlandia: OutoKumpu Research Py
• SHON HY. and WADSWORTH ME., 1979. Rate processes of extractive metallurgy. New York: Plenum Press

Uwagi

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).