Abstract: The invention relates to a process and apparatus for the isothermal operation of heterogeneously catalyzed reactions involving at least three phases in the form of a gaseous phase, a liquid phase and a solid phase. The invention provides apparatus for carrying out reactions involving a gaseous phase, a liquid phase and a solid phase, comprising (i) a dispersing element for dispersing a gas phase in a liquid phase to generate a reaction fluid, (ii) at least one reactor which possesses an inlet, an outlet and a reactor space bounded by heat-removing walls which are spaced apart substantially uniformly along the main flow axis of the reaction fluid, and which is fitted with catalyst-coated metal fabric, and (iii) a feed line which routes the reaction fluid from the dispersing element to the reactor inlet and is sufficiently short that the degree of dispersion of the reaction fluid does not substantially change in the course of the passage through the feed line.

Abstract: The invention relates to catalyst packing and a production process for catalyst packing in which a fabricated woven or knitted fabric in the form of continuous web goods is shaped to give a package by stacking a plurality of layers, and segments (S) are cut out of the package and assembled to give one or more course(s) which completely fill the reactor cross section. A reactor containing catalyst packing of this type is particularly suitable for catalytic reactions, preferably for hydrogenations, selective hydrogenations, selective oxidations or isomerizations.

Abstract: In a process for the suspension hydrogenation of an anthraquinone compound or a mixture of two or more thereof in a reactor in which there are present the working solution in which at least one catalyst is suspended and, in addition, a hydrogen-containing gas phase, the working solution and the gas phase are, in the reactor, passed at least partly through a fitting having openings or channels whose hydraulic diameter is from 0.5 to 20 mm, preferably from 1 to 10 mm, particularly preferably from 1 to 3 mm.

Abstract: A process for hydrogenating an anthraquinone compound or a mixture of two or more thereof utilizes specific catalysts comprising, as active metal, a metal of transition group VIII of the Periodic Table of the Elements.

Abstract: Active compositions are deposited by means-of an impregnating process onto structured supports, where the impregnating medium has a surface tension of not more than 50 mN/m. Monoliths are made from the structured supports thus produced. The structured supports or the monoliths are used as catalysts in chemical processes.

Abstract: An &agr;,&bgr;-unsaturated carbonyl compound of formula (I) where R1 is saturated C1-40-hydrocarbyl or a substituted or unsubstituted aromatic radical containing moiety, and R2, R3 and R4, independently of one another, are hydrogen or a C1- to C4-alkyl group, is selectively hydrogenated in the liquid phase to a saturated carbonyl compound of formula (II) with hydrogen in the presence of a pulverulent palladium and/or rhodium catalyst and in the presence of an organic base, by conducting the hydrogenation in a packed bubble column reactor in which product is recycled and hydrogen gas is recirculated.

Abstract: Alkenes are prepared by partial hydrogenation of alkynes in the liquid phase at from 20 to 250° C. and hydrogen partial pressures of from 0.

Abstract: A catalyst packing which can be produced by vapor deposition and/or sputtering of at least one substance active as catalyst and/or promotor onto woven or knitted fabrics or sheets as support material is used in a process for catalytic distillation in which a heterogeneously catalyzed reaction is combined with a simultaneous distillation or rectification over the catalyst packing.

Abstract: The fixed-bed catalyst comprises palladium and selenium or tellurium or a mixture of selenium and tellurium on a silicon dioxide support and has a BET surface area of from 80 to 380 m2/g and a pore volume of from 0.6 to 0.95 cm3/g in the pore diameter range from 3 nm to 300 &mgr;m, with from 80 to 95% of the pore volume being in the pore diameter range from 10 to 100 nm. It is prepared by impregnating a silicon dioxide support with a solution of a palladium compound and a selenium compound or tellurium compound or a mixture of a selenium compound and a tellurium compound, drying it and reducing it in the presence of hydrogen. The catalyst is used, in particular, for isomerizing 3-buten-1-ol compounds.

Abstract: A process for preparing 1,4-butanediol by continuous catalytic hydrogenation of 1,4-butynediol comprises reacting 1,4-butynediol with hydrogen in the liquid continuous phase in the presence of a heterogeneous hydrogenation catalyst at from 20 to 300° C., a pressure of from 1 to 200 bar and values of the liquid-side volumetric mass transfer coefficient kLa of from 0.1 s−1 to 1 s−1 a) using a catalyst suspended in the reaction medium, where if a packed bubble column is employed this is operated in the upflow mode and at a ratio of gas leaving the reaction vessel to gas fed to the reaction vessel of from 0.99:1 to 0.4:1, or b) passing the liquid and gas in cocurrent in an upward direction through a fixed-bed reactor operated in the gas-circulation mode while maintaining a ratio of the gas fed to the reaction vessel to gas leaving the reaction vessel of from 0.99:1 to 0.4:1.

Abstract: The fixed-bed catalyst comprises palladium and selenium or tellurium or a mixture of selenium and tellurium on a silicon dioxide support and has a BET surface area of from 80 to 380 m2/g and a pore volume of from 0.6 to 0.95 cm3/g in the pore diameter range from 3 nm to 300 &mgr;m, with from 80 to 95% of the pore volume being in the pore diameter range from 10 to 100 nm. It is prepared by impregnating a silicon dioxide support with a solution of a palladium compound and a selenium compound or tellurium compound or a mixture of a selenium compound and a tellurium compound, drying it and reducing it in the presence of hydrogen. The catalyst is used, in particular, for isomerizing 3-buten-1-ol compounds.

Abstract: A process for the manufacture of 6-aminocaproamide, wherein methyl or ethyl 5-cyanovalerate is reacted with excess ammonia at temperatures of from 25.degree. to 200.degree. C and the resulting 5-cyanovaleramide is hydrogenated at temperatures of from 25.degree. to 200.degree. C and pressures of from 50 to 300 bars in the presence of ammonia and of supported cobalt and/or nickel catalysts. 6-Aminocaproamide is suitable for the manufacture of caprolactam.

Abstract: A process for the manufacture of 1,4-butanediol and/or tetrahydrofuran, wherein maleic acid or succinic acid is used as the starting material, butyrolactone is produced in defined stages and is hydrogenated to butanediol or tetrahydrofuran, and the by-products formed are in each case recycled to the process.

Abstract: The compound Ni.sub.5 MgAl.sub.2 (OH).sub.16.sup.. CO.sub.3.sup.. 4H.sub.2 O is precipitated from an aqueous solution containing salts of nickel, magnesium and aluminum with a carbonate or bicarbonate of an alkali metal. After this catalyst precursor has been dried, calcined and reduced with hydrogen a catalyst can be prepared which is suitable for the cracking of hydrocarbons in the presence of steam. In the steam cracking of hydrocarbons the hydrocarbon and the steam may be reacted to form a gas rich in methane in contact with this catalyst at a preheating temperature of less than 300.degree. C.

Abstract: A new catalyst for the manufacture of butynediol from formaldehyde and acetylene, based on a carbonate which contains copper, has the structure of the natural mineral manasseite, also contains magnesium or aluminum or -- in place of aluminum -- iron or chromium and is converted into the catalyst by reaction of the copper ions with acetylene.

Abstract: A two-stage process for the manufacture of methane from hydrocarbons is described. In the first stage, the hydrocarbons are converted into methane-rich gases, using the nickel catalyst described below. The cracked gases thus obtained are cooled and converted into methane-rich gases in a further catalytic process stage, using a methanization catalyst or the nickel catalyst mentioned below. To produce the nickel catalyst, the compound Ni.sub.6 Al.sub.2 (OH).sub.16.CO.sub.3.4H.sub.2 O is prepared in aqueous solution. The catalyst is obtained from this compound by drying, calcination and subsequent reduction in a stream of hydrogen whilst maintaining very specific temperature gradients between the drying stage and the calcination stage.

Abstract: The compound Ni.sub.6 Al.sub.2 (OH).sub.16. CO.sub.3. 4H.sub.2 O is isolated from aqueous solution. The catalyst is obtained from this compound by drying, calcination and subsequent reduction in a stream of hydrogen, whilst maintaining very specific temperature gradients between the drying stage and the calcination stage. A process for the manufacture of gases containing methane from hydrocarbons by steam cracking, in which the abovementioned catalyst is employed, is also described.