Process for the preparation of sulphonic acid halides The preparation of sulfonyl chlorides from the corresponding sulfonic acids has hitherto been carried out in a manner such that the acids are treated either with chlorosulfonic acid or with phosphorous pentachloride. A number of methods for the preparation of acid halides of aromatic carboxylic acids can not be transferred easily to the aromatic sulfonic acids, since the sulfonic acids behave differently in many respects from the carboxylic acids. Thionyl chloride, for example, the returns to the latter in most excellent yield chlorides and to the chlorides of phosphorus has the privilege to form only gaseous by-products is to display sulfonyl chlorides from sulfonic not appropriate because generally gives the anhydrides of the sulfonic acids. It has now been found that it is to aromatic sulfonyl halides, when treating the sulfonic acids with sulfur halides or with such mixtures, which can react with the formation of sulfur halides. Economically, the conversion of the sulfonic acid in their halides by sulfur halides or by sulfur and halogen important because, for example, chlorine and sulfur, in contrast to the expensive phosphorus chlorides extremely cheap starting materials. Also you do not need, such as in the use of chlorosulfonic acid, with very large, later working to decompose excess of chlorinating agents. The execution of the procedure turns to the following: One p-toluenesulfonic acid suspended in carbon disulfide and sulfur are added. Then it runs a current of chlorine, followed by a regular development of hydrochloric acid gas and sulfur dioxide takes place. The tear gases with sulfur chloride. It therefore works with a certain trberschuß of sulfur. The reaction takes place according to the following equation: 2 C7H7SO3H + S + 2 C12 = 2 C7H7S02Cl + SO2 + 2 HCI. Instead of carbon disulfide can use other solvents also can work without diluent. The temperature can also vary within fairly wide limits. In an analogous manner to set forth Sulfonsäurebromide. Examples 250 g of toluenesulfonic acid and 50 g of sulfur are suspended in carbon tetrachloride and treated with stirring with chlorine. The resultant heat development is prevented by external cooling. Sulfur gradually goes into solution under simultaneous escape of hydrogen chloride and sulfur dioxide. After completion of chlorine absorption water is added, partly in order to decompose excess sulfur chloride, and partly in order to remove dissolved hydrochloric acid and sulfurous acid. The carbon tetrachloride solution leaves behind after the evaporation of the solvent, 250 g of nearly pure sulfonic acid chloride, which corresponds to a yield of 90 per cent. Judging from pure p-toluenesulfonic acid, we obtain the p-toluenesulfonyl chloride, mp 68°. 5 parts by weight toluenesulfonic acid, which must be free of water and sulfuric acid, and under these conditions slightly due to extremely low crystallization rate in the liquid state is that I added weight of sulfur and treated while stirring with chlorine. The temperature is expediently maintained slightly above room heat to promote the chlorine uptake. After completion of chlorination is interrupted and in a known way, the small amounts of impurities present toluenesulfonyl as sulfur chloride, free. CLAIM: A process for preparing sulfonic acid halides from sulfonic acids, characterized in that the sulfonic acids in the presence or absence of diluents with sulfur halides or mixtures of which can react with the formation of sulfur halides treated.