Process for the purification of strong acids or strongly acidic media of divalent and higher valent metal ions

The present invention relates to a process for the purification of strong acids or strongly acidic media of divalent and higher-valent metal ions, which can be used in the context of the production of high-purity silicon dioxide. Furthermore, the invention relates to the use of special ion exchangers for carrying out the method according to the invention and the resulting high-purity silicon dioxides.