Abstract: A method for hydrogenating optionally substituted phenols with one hydroxyl group to cyclohexanones over modified, palladium-comprising supported catalysts. This is possible surprisingly in selected alcoholic solvents with high selectivity. Here it is even possible to recycle the catalysts employed, which hitherto has only been possible with considerable loss of selectivity.

Abstract: A process for the preparation of phenothiazine granules having a narrow particle size distribution, phenothiazine having a purity of at least 98% in liquid form being forced through a means provided with holes and a frequency being applied to the liquid phenothiazine and the liquid phenothiazine emerging through the holes entering a cooling medium having a temperature in the range of from ?196 to =120° C. so that the liquid phenothiazine drops thus produced are brought to a temperature below the melting point and said drops are, if required, further solidified in a downstream cooling zone.

Abstract: The invention relates to a method for producing a phenothiazine granulate with a narrow particle size distribution. At least 98% pure phenothiazine in liquid form is pressed through a device provided with boreholes and a frequency is applied to said liquid phenothiazine. The liquid phenothiazine discharged through the boreholes enters a cooling medium having a temperature of between ?196 and +120° C. The drops of liquid phenothiazine thus produced are brought to a temperature below melting point and are optionally solidified in another post-cooling area. Optionally, fine-grain particles or coarse-grained particles thus formed can be subsequently removed by appropriate methods. The bulk density of the obtained phenothiazine granulates ranges more particularly from 720–780 kg/m3.

Abstract: The invention relates to a method for producing a phenothiazine granulate with a narrow particle size distribution. At least 98% pure phenothiazine in liquid form is pressed through a device provided with boreholes and a frequency is applied to said liquid phenothiazine. The liquid phenothiazine discharged through the boreholes enters a cooling medium having a temperature of between −196 and +120° C. The drops of liquid phenothiazine thus produced are brought to a temperature below melting point and are optionally solidified in another post-cooling area. Optionally, fine-grain particles or coarse-grained particles thus formed can be subsequently removed by appropriate methods. The bulk density of the obtained phenothiazine granulates ranges more particularly from 720-780 kg/m3.

Abstract: In the process for the preparation of the dyestuff of the formula I ##STR1## by diazotization and coupling, the aqueous suspension present when the coupling has ended is heated to temperatures of 50.degree. C. up to the boiling point of the aqueous phase in the presence of a dispersing agent.