METHOD OF REPROCESSING ALKANESULFONIC ACID

The invention relates to a method of reprocessing alkanesulfonic acid employed in a chemical process as an agent, catalyst or solvent and comprising the steps of: (a) removing an alkanesulfonic acid-comprising stream from a reaction mixture generated in the chemical process, (b) feeding the alkanesulfonic acid-comprising stream into a melt crystallization as the starting melt to form crystals of the alkanesulfonic acid, of hydrates of the alkanesulfonic acid or of a mixture of both suspended in mother liquor, (c) performing a solid-liquid separation to remove the crystals from the mother liquor, (d) optionally washing the crystals to remove mother liquor adhering to the crystals, (e) recycling the washed or unwashed crystals removed from the mother liquor into the chem�ical process.