Leaching shrinking-core model

Choudhary et al. [58] found reaction controlled kinetics with an activation energy of 56.6 kJ/mol for the leaching of skeletal nickel, similar to the leaching of skeletal copper. The kinetics did not fit Levenspiel s shrinking core model [57] but it should be noted that the leaching solution was agitated with a flat stirrer at 1500 rpm. 

The shrinking core models described by Levenspiel cater for both reaction- and diffusion-controlled systems. Referring to the literature, how do these systems differ and which of these models do skeletal catalysts fit during their preparation by leaching ... 

Roman et al. developed a model for the leaching of copper oxide ores using the shrinking-core model. They found that the surface reaction is fast so that only the diffusicm term need be considered. The consumption of acid. A, is related to the copper recoveiy by the expression... 

To determine the kinetic parameters and rate-controlling step for the leaching of metals, the experimental data were analyzed according to the shrinking core model. 

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