Investigating the Effect of Lime Sub-Grains on the Modeling of Hydrogen Reduction of Molybdenum Disulfide

Document Type : Research Article

Authors

1 Department of Chemical Engineering, Shahid Bahonar University of Kerman, Kerman, I.R. IRAN

2 Faculty of Chemical Engineering, Amir-kabir University of Technology, Tehran, I.R. IRAN

Abstract

Both of the diffusion and the reaction of hydrogen, in a composed pellet of molybdenum disulfide and lime particles, have a certain role in the reduction of molybdenum disulfide process. In this study presented a mathematical model for simulating the successive gas-solid reaction of hydrogen reduction of molybdenum disulfide in the presence of lime, which evaluated the role of this two effect, diffusion and reaction. The mole and heat balance equations solved at each time and location step to obtain the concentration and temperature profiles in the pellet. The results of this modeling obtain that the non-isothermal assumption of the reaction has no effect on the behavior of the reaction. The results of this modeling have a relative deviation from experimental data. Reason of this deviation is many effective factors that affected this series of non-catalytic gas-solid reactions, reaction of one gas with two solids, which completely described in this paper. Finally calculated new values of the effective diffusivity and the frequency factor of reaction by fitting the model results to the experimental data, and the model predictions approached the experimental data, very well. In this modeling applied the dusty gas model to describe the gas diffusion in the pellet.

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