Effect of H2SO4 concentration on preparation and activity of activated manganese dioxide

In the preparation of activated manganese dioxide (AMD), H2SO4 solution is a better medium for dissolution of Mn2O3 and disproportionation of Mn3+ ions. The preparation and activity of AMD is affected greatly by the H2SO4 concentration in the solution. Mn2O3 cannot dissolve completely if the H2SO4 concentration is too low. By contrast, less porous AMD is formed if the H2SO4 concentration is too high.