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Abstract

In this study, a mathematical model was developed to describe the progress of the successive gas–solid reactions occurring in a porous pellet and the model was applied to hydrogen reduction of molybdenum disulphide in the presence of lime. To carry out a realistic modelling for the multi-step reactions, effect of the structural changes and non-isothermal conditions during the reaction within the pellet has been taken into account. The effect of structural change was implemented in the modelling through variation of the solid reactant grain sizes and effective diffusion. The results predicted by the model were evaluated and validated by comparing with the experimental data. Structural changes and non-isothermal conditions had no significant effect on the modelling results. Therefore, deviation of the model prediction from the experimental data can be ascribed to the side reaction occurring within the pellet. To compensate the effects of the side reaction, adapted parameters were obtained through the experimental data.

Keywords

Molybdenum disulphide Lime Side reaction Structural change Modelling Reduction

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An improved model of lime-enhanced reduction of molybdenum disulphide pellet by hydrogen

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