Evonik Degussa Gmbh

Evonik Stockhausen Gmbh

Evonik Industries Ag

Evonik Operations Gmbh

Axel Hengstermann

Stephan Kohlstruk

Franz-Felix Kuppinger

Robert Jansen

Joerg-Joachim Nitz

Guido Stochniol

Andreas Sabbagh

Matthias Orschel

Anne Rittsteiger

Alexander Martin Rüfer

Anja Mueller

Martin Roos

Gerda Grund

Ralf Meier

Jürgen Mosler

Günther Bub

Guido Streukens

Markus Schwarz

Martin Maier

Cord Knoop

Jan Cassens

Markus Galle

Matthias Mendorf

Anja Müller

Armin Matthias Rix

Torsten Balduf

Monika Berweiler

Martina Ortelt

Dirk Hoppe

Christian Lettmann

Stefan Nordhoff

Jörg-Joachim Nitz

Andreas Merkel

Daniel Demicoli

Bernd Guenzel

Michael Demming

Joachim Pohlisch

Stefan Röder

Sven Schneider

Sabrina Sowka

Bernd Günzel

Jens Doering

Jörg Leistner

Juergen Lippe

Jens Döring

Jan Caßens

Norbert Schlüter

Bernd-Holger Modrow

Stephan Schäflein

Michael D Hinton

Joachim Deinken

Peter Jansens

Frank Huebner

Andreas Hoff

Norbert Richter

Rolf Hirsch

Jorn Walscharts

Alexander Martin RÜFER

Dr Jürgen Mosler

Prof Dr Günther Bub

Dr Andreas Sabbagh

The present invention relates to a process for hydrogenating nitrile compounds to amino compounds, in which the cross-sectional loading of the reactor during the hydrogenation is less than or equal to 4.0 kg/m*s, based on the liquid phase.

Process for preparing amino compounds from nitrile compounds

The present invention is directed to a process for fine purification of isophoronediamine from the production of isophoronediamine wherein the crude isophoronediamine I is subjected to a fine purification by means of two vacuum distillation columns, wherein I. in the first vacuum distillation column K I low-boiling by-products still present are removed, and a crude IPDA II is transferred from the bottom of K I into the vacuum distillation column K II, II. and in the second vacuum distillation column K II the isophoronediamine is obtained in pure form overhead and separated from the organic residues, wherein the first condenser is a partial condenser and the pure IPDA is removed therein, and wherein the second condenser is a total condenser and the residual portion of the vapor stream from K II is completely condensed therein and recycled as return stream into the first vacuum distillation column K I.

Purification of crude isophoronediamine by partial condensation in series with total condensation

A process for fine purification of isophoronediamine (IPDA), including producing IPDA by aminating hydrogenation of isophorone nitrile in the presence of at least ammonia, hydrogen, a a hydrogenation catalyst and optionally further additions to obtain a crude IPDA, and subjecting the crude IPDA to a fine purification via two vacuum distillation columns, wherein in the first vacuum distillation column the removal of any remaining relatively low-boiling byproducts is effected and in the second vacuum distillation column the IPDA is obtained in pure form as tops and thus separated from the organic residues, and wherein the first vacuum distillation column has vacuum distillation column has a partial condenser fitted to it.

Coupling of distillative purification with a partial condenser for pre-purification of isophoronediamine

The present invention relates to the fine purification of isophoronenitrile (IPN) by melt crystallization.

Fine purification of isophoronenitrile by melt crystallization

Cations are removed from a substance stream that is produced during the production of isophoronenitrile with the help of a cation exchanger.

Process for removing cations from an isophoronenitrile product mixture

The invention relates to an improved process for preparing 3-aminomethyl-3,5,5-trimethylcyclohexylamine, referred to hereinafter as isophoronediamine or, in abbreviated form, IPDA, by: I. preparation of isophorone by catalyzed aldol condensations with acetone as reactant; II. reaction of isophorone with HCN to form isophoronenitrile (IPN, 3-cyano-3,5,5-trimethylcyclohexanone); III. catalytic hydrogenation and/or catalytic reductive amination (also referred to as aminative hydrogenation) of 3-cyano-3,5,5-trimethylcyclohexanone, hereinafter called isophoronenitrile or, in abbreviated form, IPN, to give the isophoronediamine.

Process for preparing 3-aminomethyl-3,5,5-trimethylcyclohexylamine

A process for preparing isophorone (3,5,5-trimethyl-2-cyclohexen-1-one) is provided wherein distillation vapors from the work-up of product fractions are recycled to earlier stages of operation of the process.

Hydrolysis of the residues obtained in the production of isophorone to recover isophorone and acetone

In one aspect, a process for the preparation of a superabsorbent polymer is described herein. In some embodiments, the process comprises (I) preparing acrylic acid, wherein the process comprises (a1) provision of a fluid F1 having a composition comprising from about 5 to about 20 wt. % of hydroxypropionic acid, salts thereof, or mixtures thereof; from about 0.1 to about 5 wt. % of inorganic salts; from about 0.1 to about 30 wt. % of organic compounds which differ from hydroxypropionic acid; from 0 to about 50 wt. % of solids; and from about 20 to about 90 wt. % of water; (a2) dehydration of said hydroxypropionic acid to give a fluid F2 containing acrylic acid; and (a3) purification of said fluid F2 to give a purified acrylic acid phase comprising acrylic acid having a purity of at least 70 wt. %; and (II) polymerizing the acrylic acid of (I) to form a superabsorbent polymer.

Superabsorbent polymers and methods of making the same

The invention relates to a method for producing isophorone by catalyzed aldol condensation of acetone as an educt, reprocessing the reaction product, hydrolyzing the product stream, and separating into an organic and an aqueous fraction, obtaining isophorone from the organic fraction, distillatively reprocessing the aqueous fraction, and feeding the vapors from the head of the distillative reprocessing apparatus into the hydrolysis apparatus.

Method for producing isophorone

A process for purifying laurolactam by means of integrated connection of distillation and crystallization is provided. The crystallization is performed as a solution or melt crystallization. The process reduces thermal stress applied to the laurolactam stream and improved yields are obtained. Raw materials are recovered and recycled in the production sequence.

Method for isolation of laurolactam from a laurolactam synthesis process stream

The present invention relates to a method for purifying an unpurified phase, containing a target product, preferably (meth)acrylic acid, water, and at least one impurity differing from the target product and from water comprising: a) crystallizing the target product and water; b) separating the crystals from the mother liquor created in step a); c) melting at least part of the separated crystals to form a melt; and d) recycling at least part of said melt to step b). The invention further relates to a method for the production of a purified phase, containing a target product and water, a method for the production of a polymer based on (meth)acrylic acid, polymers that may be obtained by means of said method, chemical products, such as fibers or molded bodies, and the use of polymers.

Method for producing and purifying aqueous phases

In one aspect, a process for the preparation of a superabsorbent polymer is described herein. In some embodiments, the process comprises (I) preparing acrylic acid, wherein the process comprises (a) provision of a fluid Fhaving a composition comprising from about 5 to about 20 wt. % of hydroxypropionic acid, salts thereof, or mixtures thereof; from about 0.1 to about 5 wt. % of inorganic salts; from about 0.1 to about 30 wt. % of organic compounds which differ from hydroxypropionic acid; from 0 to about 50 wt. % of solids; and from about 20 to about 90 wt. % of water; (a) dehydration of said hydroxypropionic acid to give a fluid Fcontaining acrylic acid; and (a) purification of said fluid Fto give a purified acrylic acid phase comprising acrylic acid having a purity of at least 70 wt. %; and (II) polymerizing the acrylic acid of (I) to form a superabsorbent polymer.

The invention relates to a washing apparatus, including a First Region () to which a wash material () is supplied, a Second Region (), in which the wash material () is washed, and a Third Region (), in which the wash material () is melted and a flow resistance (), which is provided between the Second Region () and the Third Region (), a purification apparatus, a synthesis device, a method for purifying a wash material, and the use of a washing apparatus or a purification apparatus for purifying and then using the target product obtained by the purification.

Washing apparatus, a method of purifying a wash material and use of the washing apparatus

The invention relates to a process for the preparation of acrylic acid and a process for the preparation of polyacrylic acid comprising the process steps: (a1) preparation of 3-hydroxypropionic acid from a biological material to give a fluid, in particular aqueous, phase containing 3-hydroxypropionic acid; (a2) dehydration of the 3-hydroxypropionic acid to give a fluid, in particular aqueous, solution containing acrylic acid; (a3) purification of the solution containing acrylic acid by a suspension crystallization or a layer crystallization to give a purified phase; and corresponding devices for carrying out these processes, and acrylic acid and polyacrylates. The invention is distinguished in that acrylic acid and polyacrylates can thereby be prepared efficiently, inexpensively, and sustainably with simple means and with a high purity on the basis of regenerable raw materials.

Process for preparing acrylic acid purified by crystallization from hydroxypropionic acid and apparatus therefore

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Axel Hengstermann