Abstract:
The present invention relates to a process for preparing adipic acid or at least one conversion product thereof, in which muconic acid is hydrogenated with hydrogen in the presence of at least one transition metal catalyst C and of an aqueous liquid A in a reaction zone, wherein the muconic acid is at least partly insoluble in the liquid A under the hydrogenation conditions.
Abstract:
The present invention relates to a method for hydrogenating aromatic compounds with hydrogen in the presence of a catalyst, in which the catalyst comprises ruthenium on a zirconium oxide support material, and also the use of a catalyst comprising ruthenium on a zirconium oxide support material for hydrogenating aromatic compounds.
Abstract:
The present invention relates to a process for hydrogenating 4,4′-methylenedianiline and/or polymeric MDA with hydrogen in the presence of a catalyst comprising ruthenium on a zirconium oxide support material, and also to the use of a catalyst comprising ruthenium on a zirconium oxide support material for hydrogenating 4,4′-methylenedianiline and/or polymeric MDA.
Abstract:
The invention relates to a method for producing hexamethylenediamine, wherein a) a muconic acid starting material is provided, which is selected from among muconic acid, esters of muconic acid, lactones of muconic acid, and mixtures thereof, b) the muconic acid starting material is subjected to a reaction with hydrogen in the presence of at least one hydrogenation catalyst in order to form 1,6-hexanediol, and c) the 1,6-hexanediol obtained in step b) is subjected to amination in the presence of an amination catalyst in order to obtain hexamethylenediamine. The invention further relates to hexamethylenediamine which can be produced by means of said method.
Abstract:
The invention relates to a process for preparing hexane-1,6-diol, in which a) a muconic acid starting material is provided, selected from muconic acid, esters of muconic acid, lactones of muconic acid and mixtures thereof, b) the muconic acid starting material is subjected to a reaction with hydrogen in the presence of at least one hydrogenation catalyst to hexane-1,6-diol, and c) the output from the hydrogenation in step b) is subjected to a distillative separation to obtain hexane-1,6-diol.
Abstract:
A process for the removal of acids from reaction mixtures, comprising at least one product of value which is sparingly soluble in water, by at least one unpolar amine as an auxiliary base, which includes: a) reacting the auxiliary base with the acid with formation of a salt; b) reacting the salt formed in step a) with a further base which accepts the acid with liberation of the auxiliary base and combines with the acid to be accepted from the auxiliary base to form a salt which is very readily soluble in water; c) extraction of the mixture obtained in step b) with water or an aqueous medium, wherein the salt of the further base dissolves in the aqueous phase and the product of value, or the solution of the product of value, in a suitable solvent and the auxiliary base form at least one separate nonaqueous phase; and d) removal by distillation of at least part of any solvent present from the at least one nonaqueous phase obtained in step c), to form two nonmiscible liquid phases.
Abstract:
A method for preparing a phenylcyclohexane of formula I by hydrogenation of a biphenyl of formula II with hydrogen in the presence of Raney nickel, where R1 and R2 both have the same meaning in formulas I and II and independently of one another are hydrogen atoms, C1- to C10-alkyl groups or phenyl groups, wherein the hydrogenation takes place in the presence of 0 to 20 parts by weight of water to 100 parts by weight of Raney nickel.