نوع مقاله : مقاله پژوهشی
عنوان مقاله English
نویسندگان English
In the zinc production Nickel are removed from zinc solution by cementation with zinc powder. The high consumption of zinc powder lead to increased production costs. Undoubtedly, increasing the speed and efficiency of the process can help improve the process. In this study, an attempt was made to produce zinc foam with a very high specific surface area by creating nanostructured zinc foam with nano-pore structure via the electrodeposition method. Zinc foam with a very high specific surface area was produced and used in the cementation process. The specific surface area of the obtained foams, which was measured by the BET method, was found to be between 8 and 480 m2/g. A kinetic study of the cementation rate was conducted with the produced foams in a non-continuous reactor by examining parameters such as temperature, time, pH, stirring speed, and Zinc stokiometry. The decrease in the concentration of the nickel over time was investigated, and the Avrami and shrinking core models were found to have a better fit with the obtained results. Ultimately, the Avrami kinetic model was proposed for this reaction. The results indicated that control is exerted by the diffusion of ions from the boundary layer. Temperature was found to increase the reaction rate, and the activation energy was calculated to be 4.7 kJ/mol. It was observed that increasing the temperature and stirring speed has an increasing effect on the Avrami exponent n, and the values of n increase from 0.82 to 0.9 and from 0.73 to 0.89, respectively
کلیدواژهها English
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