LEACHING KINETICS OF ZINC FROM SPHALERITE WITH ACIDIFIED SODIUM HYPOCHLORITE

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LEACHING KINETICS OF ZINIC.pdf (1.45 MB)

Date

2008-04-16

Authors

Adebayo, A. O.

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Department Chemistry,Faculty of Natural and Applied Sciences, nasarawa state university keffi.

Abstract

Investigations on the kinetics leaching of zinc from sphalerite with sodium hypochlorite in hydrochloric acid were conducted. It is found that hydrochloric and hypochlorous acids concentration have significant effects on the leaching rate of zinc, with the reaction order with respect to the sodium hypochlorite is 0.65 and 0.52 for hydrochloric acid. Temperature has inverse relations on the leaching rate with apparent activation energy of 19 kJmol1 within the temperature range of 30 to 50°C. Decrease in particle size lead to increase in the leaching rates. Changes in the speed of agitation significantly affect the leaching rates. The leaching of zinc from sphalerite under these conditions was found to be diffusional - controlled and follows a shrinking core model. Employing a graphical and statistical methods, the following kinetic model including the effect of the above chosen parameters, was established: 1 + 2(1 - a) - 3(1 - = y” [NaOClfi5[HClf2 exp(-2280/T)t

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Keywords

Sodium hypochlorite, leaching, kinetics, sphalerite

Citation

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https://keffi.nsuk.edu.ng/handle/20.500.14448/5477

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