Interaction of manganese(IV) oxide with aqueous solutions of citric and sulfuric acids

The kinetic laws of the dissolution of manganese(IV) oxide using citric acid are studied as functions of the temperature and pH of a solution and the concentration of citric acid. The following kinetic parameters of the dissolution are calculated: the reaction rate, the reaction order with respect to citrate ions (n = 0.6), and the activation energy (E a = 47.4 kJ/mol). The optimum conditions favoring an increase in the leaching intensity and economical consumption of the reactants are experimentally determined.