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Leaching kinetics of copper from chalcopyrite concentrate in nitrous-sulfuric acid

Gok O., Anderson C. G., Cicekli G., Cocen E. L.

Physicochemical Problems of Mineral Processing

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2014

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Vol. 50, iss. 1

399--413

EN

Treating chalcopyrite flotation concentrates by hydrometallurgical techniques seems to be the most convenient method for leaching copper due to concerns over air pollution and regulations regarding the emission of sulfur dioxide that result from smelting. In this study, the leaching recovery-time trajectories of bulk chalcopyrite concentrate obtained from a flotation plant in the Kastamonu region of Turkey are presented. The effects of various parameters were elucidated in the nitrous-sulfuric acid electrolyte (CNaNO2:0.05 M–0.15 M, CH2SO4:1 M) at a moderate temperature (80–120 °C). A high level of copper recovery (98%) from bulk chalcopyrite concentrate was obtained under a total pressure of 6 atm at 120°C within 2 h when using small amounts of nitrite species due to their autocatalytic behavior in acidic solutions. The kinetics were well correlated with the shrinking core model for the diffusion controlled mechanism with an apparent activation energy of 34.06 kJ·mol–1. Elemental sulfur was the primary leaching product on the mineral surface, as confirmed using XRD and SEM/EDX. The semi-empirical equation explaining the reaction rate under the present conditions was expressed as follows: ...[wzór].

2

Dual reflexivity Theorem in C*-modules

Gok O.

Demonstratio Mathematica

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2000

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Vol. 33, nr 1

131-133

3

On Reflexivity of scalar-type spectral operators

Gok O.

Demonstratio Mathematica

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1999

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Vol. 32, nr 2

433-439

4

On dual bade theorem in locally convex C(K)-modules

Gok O.

Demonstratio Mathematica

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1999

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Vol. 32, nr 4

807-810

5

Semigroups in Banach C(K)-modules and their adjoints

Gok O.

Demonstratio Mathematica

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1998

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Vol. 3, nr 3

547-552

6

Characterization of the dual center of barrelled spaces

Gok O.

Demonstratio Mathematica

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1998

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Vol. 31, nr 2

285-288