Abstract: A process for preparing (meth)acrylic acid by heterogeneously catalyzed gas phase partial oxidation of (meth)acrolein over a multimetal oxide composition which comprises the elements Mo, V and W and is obtained by a hydrothermal preparation route, and the multimetal oxide composition obtainable by this preparation route.

Abstract: The invention relates to a method for continuously producing 2-butanone from 2,3-butanediol in hot pressurized water having an added electrolyte, characterized in that a compound selected from among the group comprising Ce(SO4)2, Fe2(SO4)3, Al2(SO4) is used as the added electrolyte.

Abstract: A process for preparing (meth)acrylic acid by heterogeneously catalyzed gas phase partial oxidation of (meth)acrolein over a multimetal oxide composition which comprises the elements Mo, V and W and is obtained by a hydrothermal preparation route, and the multimetal oxide composition obtainable by this preparation route.

Abstract: The invention relates to a method for continuously producing 2-butanone from 2,3-butanediol in hot pressurized water having an added electrolyte, characterized in that a compound selected from among the group comprising Ce(SO4)2, Fe2(SO4)3, Al2(SO4) is used as the added electrolyte.

Abstract: The present invention relates to a process for the hydrolysis of nitriles of the formulae and respectively of amides of the formulae in which R is in each case hydrogen or C1-20-alkyl, to give the corresponding amides and/or acids and respectively to give the corresponding acids.

Abstract: The present invention relates to a process for the selective preparation of acetaldehyde, characterized in that acrolein and one or more ammonium salts dissolved in water are reacted continuously under high pressures and at temperatures of 300-400° C.

Abstract: The present invention relates to a process for the selective preparation of 3-methylpyridine, characterized in that acrolein and one or more ammonium salt(s) dissolved in water are reacted continuously under high pressures and at temperatures of 200-400° C.

Abstract: The present invention relates to a process for the selective preparation of acetaldehyde, characterized in that acrolein and one or more ammonium salts dissolved in water are reacted continuously under high pressures and at temperatures of 300-400° C.

Abstract: The present invention provides a process for working up isocyanate adducts, comprising the steps of a) reacting the isocyanate adducts with pure ammonia, b) working up the reaction products obtained in step a), c) recycling the amines formed into the isocyanate production.

Abstract: Crude (meth)acrylic acid is purified by a process in which a primary amine compound and an organic sulfonic acid are added to the crude (meth)acrylic acid and the latter is then worked up by distillation.

Abstract: In a process for the continuous heterogeneously catalyzed gas-phase partial oxidation of an organic compound in an oxidation reactor, whose feed gas mixture comprises, apart from the organic compound to be partially oxidized and molecular oxygen as oxidant, at least one diluent gas which is essentially inert under the conditions of the heterogeneously catalyzed gas-phase partial oxidation, where the essentially inert diluent gas consists partly of combustible gases, after passage through the oxidation reactor, the combustible constituents of the inert diluent gas present in the product gas stream leaving the oxidation reactor are not recirculated to the heterogeneously catalyzed gas-phase partial oxidation, but are put to further use for the purposes of another chemical reaction.

Abstract: Process for regenerating a silver catalyst deactivated by coking during the gas phase epoxidation of 1,3-butadiene by reacting the coked catalyst with a gas mixture containing at least 5% by volume of water vapor and up to 95% by volume of oxygen at temperatures of from 100 to 500 .degree. C.

Abstract: In a process for preparing acrolein, acrylic acid or a mixture thereof from propane, propane is partially dehydrogenated to propylene in a first stage, the product gas mixture resulting therefrom is, after separating off hydrogen and water vapor, used as feed to an oxidation reactor, the propylene formed in the dehydrogenation is partially oxidized in the oxidation reactor using molecular oxygen in the presence of non-dehydrogenated propane as inert diluent gas to give acrolein, acrylic acid or a mixture thereof and the propane present in the product gas mixture of the partial oxidation is subsequently recirculated to the dehydrogenation stage A.

Abstract: In a process for the continuous heterogeneously catalyzed gas-phase oxidation of propylene to acrolein, acrylic acid or a mixture thereof in an oxidation reactor whose feed gas mixture comprises, apart from propylene and molecular oxygen as oxidant, only at least one diluent gas which is essentially inert under the conditions of the heterogeneously catalyzed gas-phase oxidation and where, in continuous operation, at least a part of the essentially inert diluent gases present in the product gas mixture is separated off therefrom and is reused as a constituent of the feed gas mixture to the oxidation reactor, the essentially inert diluent gas mixture comprises more than 85% by volume of at least one saturated hydrocarbon having from 1 to 5 carbon atoms.

Abstract: 3,4-Epoxy-1-butene is prepared by the gas phase epoxidation of 1,3-butadiene by means of oxygen or oxygen-containing gases over silver-containing catalysts and isolation of the 3,4-epoxy-1-butene from the reaction exit mixture by performing the gas phase epoxidation in the presence of from 6 to 80 mol % of water vapor, based on the gas mixture supplied to the reactor.

Abstract: A process for the preparation of lactates by fermentation of mixtures containing sugars, conversion of the lactic acid obtained during fermentation to its salts, followed by esterification, in whicha) there is added to the fermentation liquor an alkaline earth metal carbonate or bicarbonate so as to neutralize the resultant lactic acid to a degree of at least 90 mol %,b) the resulting fermentation liquor is adjusted to pH 7 to 13 by the addition of NH.sub.3 and CO.sub.2 and the resultant precipitates are separated, andc) the resulting, purified ammonium lactate solution is esterified with an alcohol.

Abstract: A process for preparing dihydroxyacetone by condensation, catalyzed by a thiazolium ylide, of formaldehyde, wherein the reaction is carried out in a system composed of an aqueous phase and at least one organic liquid phase.

Abstract: Methacrolein is removed from a gaseous mixture by absorption by means of an aqueous solution which contains from 60 to 90% by weight of methacrylic acid.

Abstract: Compositions of the formula IMo.sub.12 P.sub.a V.sub.b X.sub.c.sup.1 X.sub.d.sup.2 X.sub.e.sup.3 Sb.sub.f Re.sub.g S.sub.h O.sub.n (I),whereX.sup.1 is potassium, rubidium and/or cesium,X.sup.2 is copper and/or silver,X.sup.3 is cerium, boron, zirconium, manganese and/or bismuth,a is from 0.5 to 3.0,b is from 0.01 to 3.0,c is from 0.2 to 3.0,d is from 0.01 to 2.0,e is from 0 to 2.0,f is from 0.01 to 2.0,g is from 0 to 1.0,h is from 0.001 to 0.5 andn is a number determined by the valency and content of the elements different from oxygen in I, are used as catalysts for preparing methacrylic acid by gas-phase oxidation of methacrolein.

Abstract: Compositions of the formula IMO.sub.12 P.sub.a V.sub.b X.sup.1.sub.c X.sup.2.sub.d X.sup.3.sub.e Sb.sub.f Re.sub.g S.sub.h O.sub.n (I)whereX.sup.1 is potassium, rubidium and/or cesium,X.sup.2 is copper and/or silver,X.sup.3 is cerium, boron, zirconium, manganese and/or bismuth,a is from 0.5 to 3.0,b is from 0.01 to 3.0,c is from 0.2 to 3.0,d is from 0.01 to 2.0,e is from 0 to 2.0,f is from 0.01 to 2.0,g is from 0 to 1.0,h is from 0.001 to 0.5 andn is a number determined by the valency and content ofthe elements different from oxygen in I, are used as catalysts for preparing methacrylic acid by gas-phase oxidation of methacrolein.