PROCESS FOR OPERATING A PLANT FOR PREPARING AN ALKANESULFONIC ACID

The present invention relates to a process for operating a plant for preparing an alkanesulfonic acid, wherein the alkanesulfonic acid is prepared by oxidation of alkylmercaptan, dialkydisulfide and/or dialkylpolysulfide and the one or more alkyl radicals of the alkylmercaptan, dialkydisulfide and/or dialkylpolysulfide are identical with the alkyl radical of the alkylsulfonic acid to be prepared.The process is characterized in that the oxidation is performed in the presence of an at least stoichiometric amount of an oxo acid of nitrogen, e.g. nitric acid, relative to the amount of the alkylmercaptan, dialkyldisulfide and/or dialkylpolysulfide during the start-up phase of the plant of the plant, wherein the start-up phase comprises the steps adding an oxo acid of nitrogen to the reactor, adding a sulfur-containing reactant progressively so that it is converted to alkanesulfonic acid, filling up the complete volume of the reactor by adding progressively sulfur-containing reactant and ifneeded oxo acid of nitrog