Abstract: An improved process for synthesizing methacrylic acid and/or alkyl methacrylates, in particular methyl methacrylate (MMA), involves reacting acetone and hydrogen cyanide in the presence of an alkaline catalyst in a first reaction stage such that a first reaction mixture containing acetone cyanohydrin (ACH) is obtained. The process then involves working up the first reaction mixture containing acetone cyanohydrin (ACH), reacting acetone cyanohydrin (ACH) and sulfuric acid in a second reaction stage (amidation), and heating the second reaction mixture in a third reaction stage (conversion), such that methacrylamide (MAA) is obtained. The process further involves hydrolyzing or esterifying methacrylamide (MAA) with water and, optionally, alcohol, preferably water and optionally methanol, in a fourth reaction stage such that methacrylic acid or alkyl methacrylate is formed. The sulfuric acid used has a concentration of 98.0 wt % to 100.0 wt %.

Abstract: An improved process for synthesizing alkyl methacrylates, in particular methyl methacrylate (MMA), involves reacting acetone cyanohydrin (ACH) and sulfuric acid in a first reaction stage (amidation). The process then involves heating the first reaction mixture in a second reaction stage (conversion) such that methacrylamide (MAA) is obtained; and then esterifying methacrylamide (MAA) with alcohol and water, preferably methanol and water, in a third reaction stage such that alkyl methacrylate is formed. The sulfuric acid used has a concentration of 98.0 wt % to 100.0 wt %. A subsequent working up of the third reaction mixture involves least two distillations in which the byproducts methacrylonitrile (MeAN) and acetone are obtained as an aqueous heteroazeotrope at least in part in the top fraction. At least some of the aqueous heteroazeotrope is removed from the process and at least partially reintroduced into the third reaction stage.

Abstract: A process for preparing methyl methacrylate (MMA) and/or methacrylic acid (MAS) having improved yield, involves amidation, conversion, and hydrolysis/esterification. Especially high yields are obtained during the amidation and in the subsequent so-called conversion.

Abstract: The invention is concerned with catalysts for heterogeneous hydrogenation of oxo process aldehydes. The problem addressed by the invention is that of developing a catalyst containing neither chromium nor nickel. In addition, it is to enable the economically viable hydrogenation of aldehyde mixtures originating from industrial oxo processes on the industrial scale. For this purpose, the catalyst should not be reliant on costly precious metals such as Ru, Pd or Pt. This problem was solved by omitting the chromium and nickel in the preparation of a conventional Cu/Ni/Cr system, such that a catalyst wherein only copper occurs as hydrogenation-active component on the support material thereof, and not chromium or nickel, is obtained. What is surprising here is that a functioning catalyst for the purpose intended still arises at all even though two of three hydrogenation-active metals are omitted.

Abstract: The invention is concerned with catalysts for heterogeneous hydrogenation of oxo process aldehydes. The problem addressed by the invention is that of developing a catalyst containing neither chromium nor nickel. In addition, it is to enable the economically viable hydrogenation of aldehyde mixtures originating from industrial oxo processes on the industrial scale. For this purpose, the catalyst should not be reliant on costly precious metals such as Ru, Pd or Pt. This problem was solved by omitting the chromium and nickel in the preparation of a conventional Cu/Ni/Cr system, such that a catalyst wherein only copper occurs as hydrogenation-active component on the support material thereof, and not chromium or nickel, is obtained. What is surprising here is that a functioning catalyst for the purpose intended still arises at all even though two of three hydrogenation-active metals are omitted.

Abstract: The invention relates to a process for the preparation of alcohols by hydrogenation of aldehydes, in which use mixture comprising at least one aldehyde and at least one accompanying component is brought into contact, in the presence of hydrogen, with a heterogeneous catalyst, giving a product mixture which comprises at least the alcohol corresponding to the hydrogenated aldehyde, and at least one by-product, where the catalyst comprises a support material, and nickel and copper applied thereto. The invention also includes a chromium-free catalyst suitable for hydrogenating aldehyde mixtures with different chain lengths, in particular those which originate from different hydroformylations and can also comprise substances with C?C double bonds.

Abstract: The invention relates to a process for the preparation of alcohols by hydrogenation of aldehydes, in which use mixture comprising at least one aldehyde and at least one accompanying component is brought into contact, in the presence of hydrogen, with a heterogeneous catalyst, giving a product mixture which comprises at least the alcohol corresponding to the hydrogenated aldehyde, and at least one by-product, where the catalyst comprises a support material, and nickel and copper applied thereto. The invention also includes a chromium-free catalyst suitable for hydrogenating aldehyde mixtures with different chain lengths, in particular those which originate from different hydroformylations and can also comprise substances with C?C double bonds.

Abstract: Method for producing acrylic acid by dehydration of a C3 hydroxycarboxylic acid, characterized in that dehydration is achieved by contacting, at a temperature of more than 150° C., the hydroxycarboxylic acid with a mixture which is liquid at this temperature and comprises at least one metal salt of a C3 hydroxycarboxylic acid, and water.

Abstract: Method for producing acrylic acid by dehydration of a C3 hydroxycarboxylic acid, characterized in that dehydration is achieved by contacting, at a temperature of more than 150° C., the hydroxycarboxylic acid with a mixture which is liquid at this temperature and comprises at least one metal salt of a C3 hydroxycarboxylic acid, and water.

Abstract: The invention relates to a method for the oxidation of a primary or secondary alcohol, preferably to form an aldehyde or ketone, comprising the following steps: a) providing a catalyst composition comprising at least one compound containing a nitroxyl radical, at least one NO source, at least one carbon or mineral acid or an anhydride of a carbon or mineral acid; b) producing a reaction mixture by adding at least one primary or secondary alcohol and a gas comprising oxygen and optionally one or more than one solvent to the catalyst composition from step a) or step e); c) incubating the reaction mixture from step b) at a temperature of between 0 and 100° C. or at the boiling point of the solvent; d) simultaneously with or subsequent to step c): crystallizing the reaction product; and e) recovering the catalyst composition by removing the crystallized reaction product from the reaction mixture obtained in step d).

Abstract: The present invention relates to a chemocatalytic liquid-phase process for the direct one-stage amination of alcohols to primary amines by means of ammonia in high yields using a catalyst system containing at least one transition metal compound and a xantphos ligand.

Abstract: The invention relates to a process for preparing primary amines which comprises the process steps A) provision of a solution of a secondary alcohol in a fluid, nongaseous phase, B) contacting of the phase with free ammonia and/or at least one ammonia-releasing compound and a homogeneous catalyst and optionally C) isolation of the primary amine formed in process step B), characterized in that the volume ratio of the volume of the liquid phase to the volume of the gas phase in process step B is greater than or equal to 0.25, and/or in that the ammonia is used in process step B) in a molar ratio based on the hydroxyl groups in the secondary alcohol of at least 5:1.

Abstract: The present invention relates to a process for preparing primary amines comprising the process steps A) provision of a solution of a primary alcohol in a fluid, nongaseous phase, B) contacting of the phase with free ammonia and/or at least one ammonia-releasing compound and a homogeneous catalyst and optionally C) isolation of the primary amine formed in process step B), characterized in that the volume ratio of the volume of the liquid phase to the volume of the gas phase in process step B is greater than 0.05 and/or in that process step B is carried out at pressures greater than 10 bar.

Abstract: The invention relates to a method for the oxidation of a primary or secondary alcohol, preferably to form an aldehyde or ketone, comprising the following steps: a) providing a catalyst composition comprising at least one compound containing a nitroxyl radical, at least one NO source, at least one carbon or mineral acid or an anhydride of a carbon or mineral acid; b) producing a reaction mixture by adding at least one primary or secondary alcohol and a gas comprising oxygen and optionally one or more than one solvent to the catalyst composition from step a) or step e); c) incubating the reaction mixture from step b) at a temperature of between 0 and 100° C. or at the boiling point of the solvent; d) simultaneously with or subsequent to step c): crystallizing the reaction product; and e) recovering the catalyst composition by removing the crystallized reaction product from the reaction mixture obtained in step d).

Abstract: The present invention relates to a chemocatalytic liquid-phase process for the direct one-stage amination of alcohols to primary amines by means of ammonia in high yields using a catalyst system containing at least one transition metal compound and a xantphos ligand.

Abstract: The present invention relates to a process for preparing primary amines comprising the process steps A) provision of a solution of a primary alcohol in a fluid, nongaseous phase, B) contacting of the phase with free ammonia and/or at least one ammonia-releasing compound and a homogeneous catalyst and optionally C) isolation of the primary amine formed in process step B), characterized in that the volume ratio of the volume of the liquid phase to the volume of the gas phase in process step B is greater than 0.05 and/or in that process step B is carried out at pressures greater than 10 bar.

Abstract: The invention relates to a process for preparing primary amines which comprises the process steps A) provision of a solution of a secondary alcohol in a fluid, nongaseous phase, B) contacting of the phase with free ammonia and/or at least one ammonia-releasing compound and a homogeneous catalyst and optionally C) isolation of the primary amine formed in process step B), characterized in that the volume ratio of the volume of the liquid phase to the volume of the gas phase in process step B is greater than or equal to 0.25, and/or in that the ammonia is used in process step B) in a molar ratio based on the hydroxyl groups in the secondary alcohol of at least 5:1.

Abstract: The invention relates to methods for producing aldehydes and the oxidation and reduction products thereof.

Abstract: The invention relates to a method for producing aldehydes and ketones from easily accessible primary and secondary alcohols by oxidation with atmospheric oxygen or pure oxygen using a catalyst system which consists of a derivative of a free nitroxyl radical.