Bayer Materialscience Ag

Covestro Deutschland Ag

Bayer Aktiengesellschaft

Bayer Materialscience, LLC

Covestro Intellectual Property Gmbh & Co. Kg

Joachim Zechlin

Dietmar Wastian

Tim Loddenkemper

Michael Schelhaas

Georg Ronge

Kai Verkerk

Wilfried Pinke

Katrin Joschek

Friedhelm Steffens

Gerhard Wegener

Thomas Bludowsky

Manfred Jautelat

Bernd Pennemann

Volker Michele

Andreas Hoffmann

Wolfgang Taube

Qiang Wei

Zhangyong Ming

Hans Warlimont

Yuguo Gai

Bodo Temme

Wenbin Ji

Thomas Stetten

Kartin Joschek

Lothar Duda

Ji Wenbin

The present invention relates to a process for preparing an isocyanate comprising the steps of (A) reacting an amine with a stoichiometric excess of phosgene using an aromatic solvent of formula CHCl, wherein X=1 or 2, (a) as a diluent during the reaction and/or (b) as a means for cooling the reaction mixture formed from the reaction of the amine with phosgene (so-called quench) to obtain (optionally after a decompression) a liquid product mixture comprising the isocyanate and the aromatic solvent employed and a gaseous product mixture containing phosgene and hydrogen chloride; followed by (B) isolating the isocyanate from the liquid product mixture obtained in step (A) comprising the step of a final distillation in which the isolated isocyanate is obtained as a product stream, wherein in the final distillation or in a distillation step upstream of the final distillation at least one stream comprising aromatic solvent of formula CHCl, wherein Y=X+1, is (at intervals or continuously) discharged such that the isolated isocyanate has a mass fraction, based on its total mass, of aromatic solvent of formula CHClin the range from 0.0 ppm to 9.9 ppm, preferably 0.0 ppm to 5.0 ppm, particularly preferably 0.0 ppm to 3.0 ppm.

Method for producing isocyanates

A process for quenching, in a quenching zone, a gaseous reaction mixture that includes a diisocyanate, phosgene and hydrogen chloride that is obtained in a reaction zone upstream of the quenching zone by phosgenation of a diamine in the gas phase. The process includes injecting a deposit preventing liquid in a deposit preventing zone located between the reaction zone and the quenching zone by passing the deposit preventing liquid through spray nozzles for the deposit preventing liquid at the entrance to the deposit preventing zone. Each spray nozzle for the deposit preventing liquid sprays the deposit preventing liquid (i) onto a wall segment of the deposit preventing zone that is adjacent to said spray nozzle for the deposit preventing liquid to produce a film of the deposit preventing liquid flowing along the wall, and/or (ii) to areas in a cross-sectional plane of the deposit preventing zone before the entrance to the quenching zone.

Process for quenching a gaseous reaction mixture obtained in the gas phase phosgenation of diamines

The invention relates to a method for producing isocyanates by phosgenating the corresponding primary amines in the gas phase, wherein the raw gaseous reaction product mixture is cooled and partially condensed by being brought into contact with at least one flow of a quenching liquid, and using a part of the condensed reaction product mixture as a component, optionally the only component, of the at least one flow of the quenching liquid after an additional cooling process. The quenching liquid used in total comprises, based on the total mass, organic solvents in a proportion of maximally 25% by mass, and the remainder of up to 100% by mass consists of at least the isocyanate to be produced. Furthermore, the reaction product mixture components which are not condensed under the influence of the quenching liquid are freed of isocyanate components in a scrubber column, and a scrubber liquid- and isocyanate-containing liquid flow is obtained with, based on the total mass, a content of organic solvents of 0.0% by mass up to 10% by mass, in particular 0.0% by mass up to 5.0% by mass.

Method for producing isocyanates in the gas phase

The invention relates to the production of isocyanates by means of phosgenation of the corresponding primary amines in the gas phase, wherein the reactant flows of amine and phosgene are fed separately to a reactor through a pre-heated inert gas flow. Isocyanates within the sense of the invention are, in the broadest sense, all isocyanates whose corresponding amines can be substantially converted into the gas phase without decomposing, with the exception of 1,5-pentane diisocyanate.

The invention relates to a process for the production of toluene diisocyanate, in which the crude toluenediamine obtained from the hydrogenation is purified and then phosgenated. The purification step reduces the total amount of cyclic ketones to less than 0.1% by weight, based on 100% by weight of the toluenediamine.

Process for the production of toluene diisocyanate

The invention relates to a process for the production of Raney nickel catalysts. In this process, the melt of an alloy comprising from 40 to 95 wt. % aluminum, from 5 to 50 wt. % nickel, 0 to 20 wt. % iron, from 0 to 15 wt. % of one or more transition metals selected from the group consisting of cerium, cerium mixed metal, vanadium, niobium, tantalum, chromium, molybdenum and manganese, and, optionally, additional glass-forming elements, is brought into contact with one or more rotating cooling rollers or cooling plates and is allowed to cool and solidify thereon. The cooling rollers have a surface structured by means of transverse grooves, and the cooling plates have a surface structured by means of grooves extending outwards from the axis of rotation. The rapidly solidified alloy on the cooling rollers or the cooling plates is then subjected to treatment with one or more organic or inorganic bases.

Process for the production of Raney nickel catalysts and their use in the hydrogenation of organic compounds

The present invention relates to a process for producing 5-nitro-3,4-dihydro-1(2H)-naphthalinone, 1,5-naphthalenediamine and 1,5-naphthalene diisocyanate, in which 4-(2-nitrophenyl)-n-butyronitrile is converted to 4-(2-nitrophenyl)-n-butyric acid.

Process for producing 5-nitro-3,4-dihydro-1(2H)-naphthalinone, 1,5-naphthalenediamine and 1,5-naphthalene diisocyanate

Process for producing 5-nitro-3,4-dihydro-1(H)-naphthalinone, 1,5-naphthalenediamine and 1,5-naphthalene diisocyanate

Process for producing 5-nitro-3,4-dihydro-1(2H)-naphthalinone, 1-5-naphthalenediamine and 1,5-naphthalene diisocyanate

The invention relates to a process for the production of 1,5-naphthalenediamine and to the intermediates 4-(2-nitrophenyl)butyronitrile, 5-nitro-3,4-dihydro-1(2H)-naphthyl-imine, 5-nitroso-1-naphthylamine, 5-nitro-1-naphthylamine, 4-(2-aminophenyl)-butyronitrile, 5-amino-3,4-dihydro-1(2H)-naphthalene imine, 4-(2-nitrophenyl)ethyl butyrate and 4-(2-nitrophenyl)butyramide obtainable during the process.

Process for the production of 1,5-naphthalenediamine

1,4-diaminonaphthalene and/or 1,5-diaminonaphthalene are produced by (a) reacting naphthalene with a halogen, (b) optionally, separating 1,4-dihalogen naphthalene or 1,5-dihalogen naphthalene from the mixture from step (a), and (c) reacting the mixture from step (a) or the 1,4-dihalogen naphthalene or the 1,5-dihalogen naphthalene from step (b) with ammonia and/or an organic amine in the presence of a catalyst.

Process for preparing 1,4-diaminonaphthalene and/or 1,5-diaminoNaphthalene

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Neuss, Germany

Joachim Zechlin