Abstract: A method for producing a target compound includes distributing a feed mixture at a temperature in a first temperature range to a plurality of parallel reaction tubes of a shell-and-tube reactor, and subjecting the feed mixture in first tube sections of the reaction tubes to heating to a temperature in a second temperature range and in second tube sections of the reaction tubes arranged downstream of the first tube sections to oxidative catalytic conversion using one or more catalysts. A gas mixture flowing out of the second tube sections is brought into contact in third tube sections arranged downstream of the second tube sections with a catalyst which has a volumetric activity below the highest volumetric activity of the one or the plurality of catalysts arranged in the second tube sections. A gas mixture from the third tube sections is withdrawn from the shell-and-tube reactor without further catalytic conversion.

Abstract: A method for producing a target compound, includes distributing feed mixture at a temperature in a first temperature range to a plurality of parallel reaction tubes of a shell-and-tube reactor. The method further includes subjecting the feed mixture in first tube sections of the reaction tubes to heating to a temperature in a second temperature range, and in second tube sections of the reaction tubes arranged downstream of the first tube sections to oxidative catalytic conversion using one or more catalysts arranged in the second tube sections. The heating is performed, at least in part, using a catalyst arranged in the first tube sections and having a light-off temperature in the first temperature range.

Abstract: A process for producing a target compound includes forming a feed mixture containing at least one reactant compound. The feed mixture is distributed to parallel reaction tubes of one or more shell-and-tube reactors and subjected to oxidative catalytic conversion in the reaction tubes. Steam is added to the feed mixture in an amount such that a steam fraction of the feed mixture is 5 to 95 vol %, oxygen is added to the feed mixture in the form of a fluid containing at least 95 vol % oxygen, and the oxidative catalytic conversion is carried out using one or more catalysts containing the metals molybdenum, vanadium, niobium and optionally tellurium.

Abstract: A magnetic stirrer (1) has a two-part housing (2), wherein the lower part (3) contains a drive motor (5) and its controlling, while the upper part (4) forms the mounting surface for a stirring container that holds the stirring magnet, and wherein the separating surface of the two parts (3) and (4) runs approximately horizontal when in the working position. The upper part (4) of this housing (2) is made of glass and the edge (8) of this upper part (4), when in its working position, is tightly pressed against an opposing surface (9) of the lower part (3), and is possibly even bonded thereto. The edge (8) can have a widening (10) that engages into a corresponding undercut (11) of the lower part (3). This provides a very simple and economical design for the magnetic stirrer (1), but one which is nevertheless also tightly sealed and impervious to aggressive vapors.

Abstract: A kneading machine with a charging opening leading to a kneading chamber, in which two axially parallel kneading tools can be driven in opposite directions at different rotational speeds, has at least three such kneading chambers which are disposed next to each other and an aperture which connects their internal spaces. The material to be kneaded can be conveyed through this aperture, which extends transversely of the shafts of the kneading tools from one kneading chamber to the next, so that the material is continuously treated until it reaches in the last kneading chamber an evacuating opening and preferably an evacuating worm which is mounted at such location and by means of which the material is ultimately evacuated from the machine. In this manner, the advantages of a kneading machine with shafts for kneading tools which are journalled at both ends are combined with the advantages of continuous treatment of the material to be kneaded.