Abstract: In a process for the preparation of acrylic acid by heterogeneously catalyzed gas-phase oxidation of propene with molecular oxygen in a reaction zone, the catalytically active material is a multimetal oxide which contains the elements Mo, V, Te and/or Sb and has a specific structure.

Abstract: A process for preparing arrays of two or more heterogeneous catalysts, heterogeneous catalyst precursors, or combinations thereof in a body having preferably parallel through-channels. In this process, a solution, emulsion or dispersion of elements present in the catalyst, catalyst precursor, or combination thereof, is first prepared, and is used to simultaneously or successively coat the channels of the body to produce freshly impregnated moist channels. These channels are then treated and reacted with one or more reactive gases, and the coated body is optionally heated in the presence or absence of inert or reactive gases.

Abstract: A process for the heterogeneously catalyzed gas-phase partial oxidation of acrolein to acrylic acid over a multimetal oxide material having a specific structure, which contains the elements Mo and V, at least one of the elements Te and Sb and at least one of the elements from the group consisting of Nb, Ta, W and Ti and is doped with promoter elements, is described.

Abstract: The invention relates to a process for preparing cyclohexanedicarboxylic acids or derivatives thereof, such as esters and/or anhydrides, encompassing the reaction of diene/maleic acid anhydride mixtures, in particular of butadiene/maleic acid anhydride mixtures or of mixtures of maleic acid anhydrides and C5-dienes to give alkyl-substituted or unsubstituted cyclohexenedicarboxylic acid anhydrides in the condensed phase, ester formation, and then hydrogenation to give the corresponding cyclohexanedicarboxylic acid derivative, and also to the use of the cyclohexanedicarboxylic acids or derivatives thereof prepared according to the invention as plasticizers for plastics.

Abstract: The invention relates to a novel structured catalyst bed which optionally comprises at least one part bed comprising at least one catalytically active mixture of oxides of the main group metals and transition metals and additionally comprises at least one catalytically active part bed comprising at least silver, at least one alkali metal and a porous support material and finally and necessarily at least one catalytically active part bed comprising at least one alkali metal phosphate and at least one sheet silicate.

Abstract: The invention relates to a method for producing acrylic acid by the heterogeneously catalysed gas-phase oxidation of propane on a multi-metal oxide mass, said mass containing the elements Mo, V, Te and/or Sb and having a specific X-ray diffractogram.

Abstract: The invention relates to a catalyst which contains a catalytically active quantity of at least one oxygen-containing molybdenum and/or wolfram compound on an oxidic support material and which has been calcinated at temperatures of 400 to 900° C. after the precursor compound of the catalytically active compounds have been applied to the support material or to a support material precursor. The transport pores for this catalyst each have a diameter of >25 nm and a volume of at least 50 mm3/g. The catalyst contains x &mgr;mol (wolfram and/or molybdenum)/m2 molybdenum and/or wolfram, with 10.1<x<20.9 in relation to the finished catalyst, with the oxidic support material having a BET surface area of 135 to 220 m2/g. Catalysts of this type are characterized by an acidity of at least 70 &mgr;mol/g at pKs<−3 in the dry state and are therfore very active. The invention also relates to a method for producing a catalyst of this type and to the preferred use thereof.

Abstract: The invention relates to a method for combinatorially producing a library of materials by means of an electrochemical deposition in an array. The inventive library is made from an array of containers that consist of an electroconductive material, are open to the top and are electroconductively connected to a shared current supply device and is made from a corresponding array of auxiliary electrodes that are electroconductively connected to a shared current supply device and are arranged in such a way that an auxiliary electrode plunges into a container respectively or can be introduced therein without touching said container. The inventive method comprises the following steps: filling the containers with electrolytes having different compositions and containing electrolytically separable elements and applying an electric voltage between the current supply devices of the containers and auxiliary electrodes for obtaining an electrolytic deposition on the surfaces of the containers.

Abstract: In a process for the combinatorial production of a library of materials in the form of a two-dimensional matrix in the surface region of a planar substrate by sputtering, the planar target used for the sputtering is arranged in parallel to the planar substrate and has surface regions of different chemical composition.

Abstract: Reactor membranes advantageously useful in oxidation reactions of hydrocarbons involving oxygen comprise a selective oxidation catalyst on a mixed conducting, oxide ion selective ceramic membrane of the composition (Sr1-xCax)1-yAyMn1-zBzO3-&dgr;, where

Abstract: A process for preparing arrays of heterogeneous catalysts and/or their precursors, made up of a body which has, preferably parallel, through-channels and in which at least n channels comprise n different heterogeneous catalysts and/or their precursors, where n is 2, preferably 10, particularly preferably 100, comprises the following steps:

Abstract: Enol ethers of the formula I where R1 is an aliphatic, cycloaliphatic, araliphatic, aromatic or heterocyclic radical which may carry further substituents which do not react with acetylenes or allenes, and the radicals R, independently of one another, are hydrogen or aliphatic, cycloaliphatic, araliphatic, aromatic or heterocyclic radicals, which may be bonded to one another to form a ring, and m is 0 or 1, are prepared by reacting an acetal or ketal of the formula II with an acetylene or allene of the formula III or IV where R and R1 have the abovementioned meanings, in the gas phase at elevated temperatures in the presence of a zinc- or cadmium- and silicon- and oxygen-containing heterogeneous catalyst.

Abstract: Multimetal oxides containing Mo, V and at least one of the elements W, Nb, Ti, Zr, Hf, Ta, Cr, Si and Ge and having a special three-dimensional atomic arrangement are used in catalysts for the catalytic gas-phase oxidation of organic compounds.

Abstract: Unsaturated ketones of the formulae Ia and Ib are prepared by a process consisting of the combination of the following reactions: a) The conventional reaction of an allyl alcohol of the formula IIa or a propargyl alcohol of the formula IIb with an isopropenyl ether of the formula III with formation of a ketal of the formula IV as a byproduct, b) preparation of the isopropenyl ether of the formula III by reacting a ketal of the formula IV with propyne or allene, or a mixture thereof in the gas phase at elevated temperatures in the presence of a heterogeneous catalyst containing zinc or cadmium together with silicon or oxygen, and c) feeding the ketal of the formula IV formed in the reaction (a) into stage (b) for the preparation of the isopropenyl ether of the formula III again.

Abstract: Multimetal oxide materials containing molybdenum, vanadium, copper and one or more of the elements tungsten, niobium, tantalum, chromium and cerium and having a multiphase structure, and their use for the preparation of acrylic acid from acrolein by gas-phase catalytic oxidation, and oxometallates of the HT Cu molybdate structure type which contain Cu, Mo and at least one of the elements W, V, Nb and Ta.

Abstract: A process for preparing compounds of the formulae I and II ##STR1## where R.sup.1 and R have the meanings indicated in the specification by an addition reaction of a compound of the formula IIIR.sup.1 OH IIIwith an acetylene or allene of the formula IV or V ##STR2## in the gas phase at elevated temperatures in the presence of a heterogeneous catalyst. The catalyst is obtained by impregnating silica with a zinc salt, by a process in which the reaction is carried out at below 200.degree. C. and the catalyst contains, as an active component, an X-ray amorphous zinc silicate or cadmium silicate containing from 1 to 40% by weight, calculated as oxide, of zinc or cadmium, obtainable by applying a salt of zinc or cadmium and an inorganic oxo acid, which salt is decomposable at below 400.degree. C., to amorphous silica and forming the catalyst before the reaction at from 50 to 500.degree. C. or during the reaction in situ at from 50 to 200.degree. C.

Abstract: Compounds of the formula I and II ##STR1## where R.sup.1 is hydrogen or an aliphatic, cycloaliphatic, araliphatic, aromatic or heterocyclic radical or an acyl radical, it being possible for these radicals to carry further substituents which do not react with acetylenes or allenes, and the radicals R, independently of one another, are hydrogen or aliphatic, cycloaliphatic, araliphatic, aromatic or heterocyclic radicals which may be linked to one another with formation of a ring and m is 0 or 1, are prepared by an addition reaction of a compound of the formula IIIR.sup.1 OH IIIwith an acetylene or allene of the formula IV or V ##STR2## where R.sup.

Abstract: A method for gas-phase oxidation of an organic compound such as acrolein is provided, which includes oxidizing the organic compound with an oxidizing agent in the presence of a catalyst, to produce a product such as acrylic acid, wherein the catalyst includes a multimetal oxide material having at least two phases and of the formula III{A}.sub.p {B}.sub.q (III),wherein ##EQU1## M.sup.1, M.sup.2, a, b, c, x, M.sup.3, d, e, y, p and q are defined in the claims,which contains the moiety {A}.sub.p in the form of three-dimensional regions A which are delimited from their local environment owing to their chemical composition differing from their local environment and are of the chemical compositionA Mo.sub.12-a-b-c V.sub.a M.sub.b.sup.1 M.sub.c.sup.2 O.sub.xand the moiety {B}.sub.q in the form of three dimensional regions B which are delimited from their local environment owing to their chemical composition differing from their local environment and are of the chemical compositionB M.sub.12.sup.3 Cu.sub.d H.sub.e O.

Abstract: Compounds of the formulae I and II ##STR1## are prepared by an addition reaction of a compound of the formula IIIR.sup.1 OH IIIwith an acetylene or allene of the formula IV or V ##STR2## where R.sup.1 and R are as defined, in the gas phase at elevated temperatures in the presence of a heterogeneous, silicate-containing catalyst, by a process in which the catalyst used is one which contains or consists of, as the active component, a zinc silicate obtained by precipitation in aqueous solution from a soluble silicon compound and zinc compound, zinc silicate beinga) an essentially X-ray amorphous zinc silicate of the formula VIZn.sub.a Si.sub.c O.sub.a+2c-0.5e (OH).sub.e.fH.sub.2 O VI,where e is from 0 to 2a+4c and the ratio a:c is from 1 to 3.5, and the ratio f:a is from 0 to 200, and/orb) a crystalline zinc silicate having the structure of hemimorphite of the formula Zn.sub.4 Si.sub.2 O.sub.7 (OH).sub.2.H.sub.2 O.

Abstract: Multimetal oxide materials containing molybdenum, vanadium, copper and one or more of the elements tungsten, niobium, tantalum, chromium and cerium and having a multiphase structure, and their use for the preparation of acrylic acid from acrolein by gas-phase catalytic oxidation, and oxometallates of the HT Cu molybdate structure type which contain Cu, Mo and at least one of the elements W, V, Nb and Ta.