Basf Aktiengesellschaft

Basf Se Corporation

Basfaktiengesellschaft

Andreas Tenten

Hartmut Hibst

Signe Unverricht

Ulrich Hammon

Otto Machhammer

Heiko Arnold

Hans-Peter Neumann

Peter Weidlich

Wilhelm Ruppel

Laszlo Marosi

Frieder Borgmeier

Frank Rosowski

Klaus Harth

Gerd Linden

Harald Jachow

Sebastian Storck

Werner Hefner

Friedrich-Georg Martin

Herbert Vogel

Susanne Haupt

Gerhard Cox

Ulrike Wegerle

Thomas Mackewitz

Jens Weiguny

Klaus Joachim M&uuml;ller-Engel

Michael Hesse

Ekkehard Schwab

Peter Zehner

Rolf-Hartmuth Fischer

Ulrich Steinbrenner

Jochen Petzoldt

Hartwig Voss

Claus Hechler

Christoph Sigwart

Klaus Joachim Müller-Engel

Goetz-Peter Schindler

Martin Haubner

Stefan Bitterlich

Michael Baier

Theo Proll

Thomas Narbeshuber

Herbert Exner

Ingolf Voigt

Hans-Josef Wolf

Gerd Bohner

Hans-Peter Schildberg

Walter Doerflinger

Veronika Kohl

Ute Pippardt

A process is described for preparing phthalic anhydride by catalytic gas phase oxidation of o-xylene, in, in a main reactor, a gaseous mixture of o-xylene and an oxygenous gas is passed through at least two reaction zones whose temperature can be controlled independently, and converted to a gaseous intermediate reaction product which comprises unconverted o-xylene, phthalic anhydride underoxidation products and phthalic anhydride, and the intermediate reaction product is introduced into a postreactor, wherein the temperature of the reaction zones in the main reactor is regulated in such a way that the concentration of unconverted o-xylene in the intermediate reaction product is at least 0.5% by weight. The process allows an increase in the overall yield of phthalic anhydride without or without significant deterioration in the product quality.

Preparation of phthalic anhydride by gas phase oxidation of o-xylene

A process is described for preparing phthalic anhydride by catalytic gas phase oxidation of o-xylene, in which a gaseous mixture of o-xylene and an oxygenous gas is converted in a main reactor to a gaseous intermediate reaction product which comprises unconverted o-xylene, phthalic anhydride underoxidation products and phthalic anhydride, the heat of reaction which arises in the main reactor being removed at least partly by indirect cooling with a heat carrier medium, and the intermediate reaction product being introduced into a postreactor. The concentration of unconverted o-xylene in the intermediate reaction product is at least 1% by weight, and the sum of the concentrations of phthalic anhydride underoxidation products in the intermediate reaction product is at least 0.5% by weight. The process allows an increase in the overall yield of phthalic anhydride without or without significant deterioration in the product quality.

Preparation of phthalic anhydride by gas phase oxidation of O-xylene in a main reactor and postreactor

A coated catalyst whose coating of active composition is a multimetal oxide comprising the elements Mo, V and Te and/or Sb can be used for the gas-phase catalytic oxidation of propane to acrylic acid.

Catalyst comprising a support and a catalytically active oxide material applied to the surface of the substrate

Process for preparing phthalic anhydride by gas-phase oxidation of xylene, naphthalene or mixtures thereof in a shell-and-tube reactor thermostatted by means of a heat transfer medium over three or more different fixed-bed catalysts arranged in zones, wherein the process is carried out so that the maximum temperature in the second catalyst zone in the flow direction is up to 50&#xb0; C. lower than the maximum temperature in the first catalyst zone and the maximum temperature in the third zone from the gas inlet is from 30 to 100&#xb0; C. lower than that in the first catalyst zone. The process of the present invention makes it possible to prepare phthalic anhydride in high yields under industrially relevant conditions.

Preparation of phthalic anhydride

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.

Method for producing acrylic acid by heterogeneously catalyzed gas-phase oxidation of propene with molecular oxygen in a reaction zone

Catalyst comprising a support body and a catalytically active oxide material applied to the surface of the substrate

A process for the catalytic gas-phase oxidation of propene to acrylic acid, in which the reaction gas starting mixture is oxidized, with a high propene loading, in a first reaction stage, over a first fixed-bed catalyst which is housed in two successive reaction zones A, B, the reaction zone B being kept at a higher temperature than the reaction zone A, and the acrolein-containing product gas mixture of the first reaction stage is then oxidized in a second reaction stage, with a high acrolein loading, over a second fixed-bed catalyst which is housed in two successive reaction zones C, D, the reaction zone D being kept at a higher temperature than the reaction zone C.

Method for the catalytic gas phase oxidation of propene into acrylic acid

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&#xb0; 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 &#x3e;25 nm and a volume of at least 50 mm/g. The catalyst contains x &#x3bc;mol (wolfram and/or molybdenum)/mmolybdenum and/or wolfram, with 10.1&#x3c;x&#x3c;20.9 in relation to the finished catalyst, with the oxidic support material having a BET surface area of 135 to 220 m/g. Catalysts of this type are characterized by an acidity of at least 70 &#x3bc;mol/g at pKs&#x3c;&#x2212;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.

Catalyst and method for producing polytetrahydrofurane

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.

Method for producing acrylic acid by the heterogeneously catalysed gas-phase oxidation of propane

A catalyst used in a process for preparing maleic anhydride by heterogeneously catalyzed gas-phase oxidation of a hydrocarbon having at least four carbon atoms by means of oxygen-containing gases comprises a catalytically active composition comprising vanadium, phosphorus and oxygen and has a essentially hollow cylindrical structure in which (a) the ratio of the height h to the diameter of the continuous hole d is not more than 1.5 and (b) the ratio of the geometric surface area A to the geometric volume V is at least 2 mm .

Hollow cylindrical catalyst and a method for producing a maleic acid anhydride

In a process for preparing maleic anhydride by heterogeneously catalyzed gas-phase oxidation of hydrocarbons having at least four carbon atoms using oxygen-containing gases in the presence of a volatile phosphorus compound over a catalyst comprising vanadium, phosphorus and oxygen in a shell-and-tube reactor unit having at least two successive cooled reaction zones, the temperature of the first reaction zone is from 350 to 450&deg; C. and the temperature of the second and further reaction zones is from 350 to 480&deg; C. and the temperature difference between the hottest reaction zone and the coolest reaction zone is at least 2&deg; C.

Method for producing maleic acid anhydride

In a process for the preparation of acrolein or acrylic acid or a mixture thereof from propane, the propane is subjected, in a first reaction stage, to a partial dehydrogenation under heterogeneous catalysis to give propene, of the components contained in the product gas mixture formed in the first reaction stage other than propene and propane at least a portion of the molecular hydrogen present is then separated off from said mixture and the product gas mixture is then used for the preparation of acrolein and/or acrylic acid by gas-phase catalytic propylene oxidation, molecular nitrogen being present for diluting the reaction gas mixture during the propylene oxidation.

Method for the production of acrolein or acrylic acid or the mixture thereof from propane

In a process for the two-stage catalytic gas-phase oxidation of propene to acrylic acid, the reaction gas starting mixture is passed, in a tube-bundle reactor, with a propene loading of &gE;160 l (S.T.P.) of propene/l&middot;h, first over a fixed catalyst bed present in two successive temperature zones A, B and then over a fixed catalyst bed which is housed either in one further temperature zone C or in two further temperature zones D, E, the temperature of the zone A being kept at a lower temperature than the zone B and the temperature of the zone D at a lower temperature than the zone E.

Method for carrying out the catalytic gas phase oxidation of propene to form acrylic acid

Oxidative reactions using membranes that selectively conduct oxygen

In a process for heterogeneously catalyzed gas-phase oxidation, a reaction gas starting mixture comprising propane, molecular oxygen and, if desired, inert gas is passed at from 300 to 500&deg; C. over a fixed-bed catalyst.

Method of heterogeneous catalyzed vapor-phase oxidation of propane to acrolein and/or acrylic acid

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Maikammer, Germany

Andreas Tenten