Abstract: The invention relates to a process for the continuous manufacture of azo pigments, wherein a coupling component is reacted, inside a reaction zone filled with a previously produced suspension of the azo pigment to be made, with an aqueous solution of a diazo component at 10.degree. to 60.degree. C. and over periods of 0.2 to 4 hours.

Abstract: The disclosure relates to a process for controlling diazotization reactions. To this end, a reaction batch containing an aromatic amine and nitrous acid is vigorously agitated so as to continuously renew the surface area of the batch. The air above said surface area is exhausted at a constant rate and tested for its content of nitrous gases originating from partially decomposed nitrous acid. Nitrous acid or dissolved matter forming it under the reaction conditions is supplied to the feed amine in the proportions necessary to provide for a content between 5 and 300 ppm nitrous gases in the exhausted air.

Abstract: The invention provides a process for the continuous diazotization of primary aromatic amines by reacting an aqueous solution or suspension of the amine in a mineral acid with an aqueous sodium nitrite solution. To this end, the lower portion of a cylindrical diazotization vessel placed in upright position is fed continuously with an aqueous mineral acid solution or suspension of a diazotizable primary aromatic amine. At the same time, the vessel is fed, via one or more inlets arranged one above the other so as to open laterally thereinto, with an aqueous sodium nitrite solution, the amine and nitrite being used in stoichiometric proportions, or the nitrite being used in a stoichiometric deficiency and the acid being used in an excess of about 1 to 3 equivalents per amine equivalent in the mineral acid solution. The resulting mixture is reacted while producing a laminar flow of liquid matter at temperatures of about 5.degree. to 30.degree. C.

Abstract: Acetic acid and acetic anhydride are produced continuously from acetaldehyde which is reacted by oxidizing it with gaseous oxygen in liquid phase in the presence of copper acylate and cobalt acylate as a catalyst and in the presence of an aliphatic carboxylic acid ester as a diluent. More specifically, the reaction is effected at temperatures of 62.degree. to 90.degree. C. over a period of less than 20 minutes with the use of the diluent and acetaldehyde in a quantitative ratio of 60:40 to 40:60; the resulting reaction products are delivered to a distilling zone in which the carboxylic acid ester and water are distilled off overhead and separated into two phases. Next, the organic phase is recycled with a reflux ratio of at least 1:1 to the distilling zone; base product accumulating in the distilling zone is delivered to an evaporating zone in which 2 to 12 parts by weight of an acetic acid/acetic anhydride-mixture as distillate are produced per part by weight of catalyst solution as base product.