Abstract: The invention relates to a method for separating ferrous ions from an iron-containing tinning electrolyte on the basis of methanesulfonic acid or phenolsulfonic acid, comprising the following steps:(a) providing a concentrated tin and iron-containing electrolyte containing 0.75 mols/l or more methanesulfonic acid phenolsulfonic acid(b) agitating and cooling the concentrated electrolyte to temperatures at which an insoluble Fe-salt preciptates(c) separating the insoluble precipitate to recover an electrolyte with a reduced iron concentration.and a recovery plant for tinning electrolytes on the basis of methanesulfonic acid or phenolsulfonic acid wherein this method is employed.