Abstract: The present invention relates to a method of preparing chlorine dioxide (ClO2) from hydrochloric acid (HCl) and sodium chlorite (NaClO2) in the presence of water (H2O). The invention has for its object to further develop the method such that it is more economical to install and operate. The object is achieved when the hydrochloric acid is used in aqueous solution at a concentration of 27 to 33 wt %, the sodium chlorite is used in aqueous solution at a concentration of 22 to 27 wt % and the molar ratio of hydrochloric acid used to sodium chlorite used is between 2.14 and 4.2.

Abstract: The invention relates to cells and a method for producing acetone.

Abstract: The present invention refers to the preparation of 3-cyano-3,5,5-trimethylcyclohexanone (isophorone nitrile, abbreviation IPN) using a calcium alkoxide, particularly calcium ethoxide, as catalyst.

Abstract: An arrangement for addition of chlorine dioxide to flowing water in a pipeline is provided. The reactants are reacted in a reaction chamber located in the flow of water and the chlorine dioxide is passed from the reaction chamber directly into the flowing water.

Abstract: 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.

Abstract: The invention describes a process for preparing acetone starting from acetyl-coenzyme A comprising process steps A. enzymatic conversion of acetyl-CoA into acetoacetyl-CoA B. enzymatic conversion of acetoacetyl-CoA into acetoacetate and CoA and C. decarboxylation of acetoacetate to acetone and CO2, which is characterized in that the coenzyme A is not transferred in process step B to an acceptor molecule. In addition, process step B is surprisingly catalyzed by enzymes of the classes of acyl-CoA thioesterase, acyl-CoA synthetase or acyl-CoA thiokinase. A completely novel metabolic pathway is concerned, because the enzymatic hydrolysis of acetoacetyl-CoA without simultaneous transfer of CoA to a receptor molecule has never previously been described for any microbial enzyme.

Abstract: The invention relates to a method for producing a low-molecular-weight organic compound, such as acetone, butanol, and ethanol, in a fermentation process. The method contains a step of introducing a gas flow into an aqueous solution containing microorganisms producing the low-molecular-weight organic compound; a step of recovering the gas flow through a compound comprising isophoron; and optionally a step of separating the low-molecular-weight organic compound from the composition comprising isophoron.

Abstract: 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.

Abstract: The invention relates to an improved process for preparing 3-aminomethyl-3,5,5-trimethylcyclohexylamine, referred to hereinafter as isophoronediamine or IPDA for short, by means of catalytic hydrogenation and/or catalytic reductive amination (also referred to as aminating hydrogenation) of 3-cyano-3,5,5-trimethylcyclohexanone, also called isophoronenitrile or IPN for short hereinafter.

Abstract: The present invention relates to a method of preparing chlorine dioxide (ClO2) from hydrochloric acid (HCl) and sodium chlorite (NaClO2) in the presence of water (H2O). The invention has for its object to further develop the method such that it is more economical to install and operate. The object is achieved when the hydrochloric acid is used in aqueous solution at a concentration of 27 to 33 wt %, the sodium chlorite is used in aqueous solution at a concentration of 22 to 27 wt % and the molar ratio of hydrochloric acid used to sodium chlorite used is between 2.14 and 4.2.

Abstract: The invention relates to a method for producing diaminodiphenyl alkanes, wherein an aromatic amine, which can be substituted or unsubstituted, is reacted with a C1-C3 aldehyde in the presence of a heterogeneous catalyst, said catalyst being a mesoporous acidic ion exchanger based on a divinylbenzene/styrene copolymer and the catalyst having acid centers in a concentration of 2 to 6 eq/kg measured according to DIN 54403 and the average pore diameter of the catalyst particles being 10 to 32 nm measured according to ASTM D 4222, and the content of polynuclear compounds in the reaction mixture being >10 and ˜15% by weight.

Abstract: The invention relates to a multi-stage process for the continuous, phosgene-free preparation of (cyclo)aliphatic diisocyanates that comprises the conversion of (cyclo)aliphatic diamines into the corresponding (cyclo)alkylene biscarbamates and the thermal cleaving of the latter into the (cyclo)alkylene diisocyanates and alcohol. The urea used in accordance with the invention and also the urea employed for the preparation of urea equivalents (e.g. alkyl carbonates, alkyl carbamates) as a possible precursor for the synthesis of the (cyclo)aliphatic biscarbamates is unconditioned.

Abstract: The present invention refers to the preparation of 3-cyano-3,5,5-trimethylcyclohexanone (isophorone nitrile, abbreviation IPN) using a calcium alkoxide, particularly calcium ethoxide, as catalyst.

Abstract: The invention relates to a method comprising the following method steps: A) providing an aqueous solution comprising microorganisms producing low-molecular, organic compounds; B) introducing at least one gas or gas mixture into the aqueous solution; C) recovering the gas flow through a compound comprising an isophoron; and optionally D) separating the low-molecular, organic compound from the composition comprising the isophoron.

Abstract: An arrangement for addition of chlorine dioxide to flowing water in a pipeline is provided. The reactants are reacted in a reaction chamber located in the flow of water and the chlorine dioxide is passed from the reaction chamber directly into the flowing water.

Abstract: 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.

Abstract: The invention relates to an improved process for preparing 3-aminomethyl-3,5,5-trimethylcyclohexylamine, referred to hereinafter as isophoronediamine or IPDA for short, by means of catalytic hydrogenation and/or catalytic reductive amination (also referred to as aminating hydrogenation) of 3-cyano-3,5,5-trimethylcyclohexanone, also called isophoronenitrile or IPN for short hereinafter.

Abstract: 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.

Abstract: Low chlorine, multi-staged method for producing cycloaliphatic diisocyanates. The invention relates to a multi-staged method for the continuous low-chlorine production of cycloaliphatic diisocyanates, comprising the synthesis of diaminodipheynl alkanes, the hydration thereof into the corresponding cycloaliphatic diamines and the subsequent conversion of cycloaliphatic diamines to the corresponding cycloalkylene biscarbamates and the thermal cleaving of the latter into the cycloaliphatic diisocyanates and alcohol.

Abstract: The invention relates to a method for producing diaminodiphenyl alkanes, wherein an aromatic amine, which can be substituted or unsubstituted, is reacted with a C1-C3 aldehyde in the presence of a heterogeneous catalyst, said catalyst being a mesoporous acidic ion exchanger based on a divinylbenzene/styrene copolymer and the catalyst having acid centers in a concentration of 4 to 6 eq/kg as measured according to DIN 54 403 and the average pore diameter of the catalyst particles being 10 to 32 nm as measured according to ASTM D 4222 10, and the content of polynuclear compounds in the reaction mixture being ?10% by weight.