Use of Pitzer’s model to calculate thermodynamic properties of aqueous electrolyte solutions of sulfuric acid

Abstract

Over this study we calculated the coefficients of activity of different species and the concentration in the presence of H+ ion when H2SO4 is alone in solution. The coefficient of average activity was calculated using the model of Pitzer. The constants of dissociation of these reactions were calculated from the values of the free standard energies. The reaction reaches a balance while producing H+, HSO4- and SO42-. The research reported here concentrated on the effect of some important operational parameters on dissolution process. The parameters were investigated and their ranges are as follows: initial molality ranging from 0.001 to 5 mol.kg-1 and temperatures between 25 and 200°C. Fortran 90 (Mathematical formula translating system) was used to perform all mathematical calculations. The numerical code can be used to calculate the molarity of ion H+ of an aqueous solution of sulfuric acid. The objective of the present work is to optimize the parameters of leaching such as activity of sulfuric acid on the dissociation phenomena.

Keywords

• Leaching
• Pitzer
• Activity
• Dissociation
• Molality

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