Basf Aktiengesellschaft

Peter M Lorz

Michael Roeper

Dieter Koeffer

Werner Bertleff

Rocco Paciello

Thomas Heidemann

Frank Rosowski

Heinz-Josef Kneuper

Peter Reuter

Bernd Bessling

Gerd Linden

Matthias Kummer

Michael Seufert

Ernst Langguth

Werner Peschel

Thomas R&uuml;hl

Bernhard Ulrich

Jean Werner Knab

Gerhard Hefele

On-spec phthalic anhydride is prepared by distillative purification of crude phthalic anhydride by a process in which crude phthalic anhydride is fed to a distillation column which is operated at reduced pressure, the low boilers are removed at the top or in the vicinity of the top of the distillation column and the on-spec phthalic anhydride is removed from the column via a side take-off.

Method for producing phthalic anhylic anhydride according to specifications

The invention relates to a method for producing shell catalysts for the catalytic vapor-phase oxidation of aromatic carboxylic acids and/or carboxylic acid anhydrides comprised of a supporting core and of catalytically active metal oxides which are deposited in a shell-shaped manner on said supporting core. The inventive catalysts are obtained by spraying an aqueous active mass suspension, said suspension containing the active metal oxides, at higher temperatures onto the hot supporting material which has a temperature ranging from 50 to 450&deg; C. The aqueous active mass suspension contains 1 to 10 wt. %, with regard to the solid content of the active mass suspension, a binding agent comprised of A) a polymerizate obtained by radical polymerization, containing 5 to 100 wt. % of monomers (a) in the form of ethylenically unsaturated acid anhydrides or ethylenically unsaturated dicarboxylic acids whose carboxyl groups can form an anhydride and containing 0 to 95 wt. % monoethylenically unsaturated monomers (b) with the provision that the monomers (a) and (b) comprise, on average, a maximum of 6 carbon atoms which are not functionalized with groups containing oxygen, and of B) an alkanolamine having at least 2 OH groups, a maximum of 2 nitrogen atoms and a maximum of 8 C-atoms, whereby the weight ratio A:B ranges from 1:0.05 to 1:1.

Method for producing shell catalysts for the catalytic vapor-phase oxidation of aromatic hydrocarbons and catalysts obtained in such a manner

Phosphorous-containing calixarenes

.omega.-Formyl-C.sub.4 -C.sub.20 -alkanecarboxylic esters are prepared by reacting C.sub.4 -C.sub.20 -alkenecarboxylic esters with carbon monoxide and hydrogen at from 30.degree. to 150.degree. C. and under from 0.01 to 30 bar in the presence of rhodium carbonyl complexes which are modified with polyphosphites.

Preparation of .omega.-formylalkanecarboxylic esters

Rhodium hydroformylation catalysts containing bisphosphite ligands of the formula I ##STR1## where -X- is a divalent bisarylene radical or R.sup.1,

Rhodium hydroformylation catalysts containing bisphosphite ligands

Rhodium hydroformylation catalysts containing bisphosphite ligands of the formula I ##STR1## where --X-- is a divalent bisarylene radical or R.sup.1,

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Mannheim, Germany

Peter M Lorz