Reaction Kinetics of Molybdenum Dissolution by Hydrogen Peroxide in Acidic and Alkaline Solutions Using Tartaric Acid and Sodium Hydroxide: a Semi-Empirical Model With Rotating Disc Method

Abstract

Molybdenum is an amphoteric metal that dissolves in both acidic and alkaline solutions. This fundamental study explores a sustainable process for the dissolution of molybdenum, focusing on the reaction kinetics in H2O2, H2O2-NaOH, and H2O2-C4H6O6 solutions. A rotating disc method was applied with the Levich's equation. Semi-empirical models with activation energy were developed for the H2O2-NaOH and H2O2-C4H6O6 solutions. The study examined the effects of rotating speed, disc surface area, temperature, H2O2, NaOH, and C4H6O6 concentrations, along with rotating speed, disc surface area, and temperature. Hydrogen peroxide significantly impacted molybdenum dissolution rates across all three solutions. The reaction order of hydrogen peroxide concentration in the H2O2 solution was greater than that of the H2O2-NaOH and H2O2-C4H6O6 solutions. The complex of molybdenum peroxo was formed in H2O2 and H2O2-NaOH solutions but decomposed at a temperature >= 50 degrees C. The activation energies were determined to be 49.90, 43.60, and 41.10 kJ/mol for the H2O2, H2O2-NaOH, and H2O2-C4H6O6 solutions. Molybdenum dissolution in H2O2-NaOH solution. image