Patent application number | Description | Published |
20100273970 | PROCESS FOR PREPARATION OF HIGH PURITY METHACRYLIC ACID - The present invention relates to a process for preparation of pure methacrylic acid, at least comprising the process steps: a) gas phase oxidation of a C4 compound to obtain a methacrylic acid-comprising gas phase, b) condensation of the methacrylic acid-comprising gas phase to obtain an aqueous methacrylic acid solution, c) separation of at least a part of the methacrylic acid from the aqueous methacrylic acid solution to obtain at least one crude methacrylic acid-comprising product; d) separation of at least a part of the methacrylic acid from the at least one crude methacrylic acid-comprising product by means of a thermal separation process to obtain a pure methacrylic acid. | 10-28-2010 |
20110306784 | METHOD FOR PRODUCING A CARBOXYLIC ACID AMIDE FROM A CARBONYL COMPOUND AND HYDROCYANIC ACID - The invention relates to a method for producing a carboxylic acid amide from a carbonyl compound and hydrocyanic acid, comprising the steps of A) reacting a carbonyl compound with hydrocyanic acid to produce a hydroxycarboxylic acid nitrile, B) hydrolysis of the hydroxycarboxylic acid nitrile obtained in step A) in the presence of a catalyst comprising manganese dioxide, wherein a molar excess of carbonyl compound is used in relation to the hydrocyanic acid to react the carbonyl compound with hydrocyanic acid according to step A), and the reaction mixture obtained in step A) is not purified by distillation before the hydrolysis according to step B) is carried out. The invention furthermore relates to a method for producing alkyl(meth)acrylates from polymers, moulding compounds and moulded bodies, wherein a method for producing a carboxylic acid amide from a carbonyl compound and hydrocyanic acid is carried out in accordance with the method described above. | 12-15-2011 |
20120232305 | METHOD FOR PRODUCING A CARBOXYLIC ACID AMIDE FROM A CARBONYL COMPOUND AND HYDROCYANIC ACID - The invention relates to a method for producing a carboxylic acid amide from a carbonyl compound and hydrocyanic acid, comprising the steps of A) reacting a carbonyl compound with hydrocyanic acid to produce a hydroxycarboxylic acid nitrile, B) hydrolysis of the hydroxycarboxylic acid nitrile obtained in step A) in the presence of a catalyst comprising manganese dioxide, wherein a molar excess of carbonyl compound is used in relation to the hydrocyanic acid to react the carbonyl compound with hydrocyanic acid according to step A), and the reaction mixture obtained in step A) is not purified by distillation before the hydrolysis according to step B) is carried out. The invention furthermore relates to a method for producing alkyl(meth)acrylates from polymers, moulding compounds and moulded bodies, wherein a method for producing a carboxylic acid amide from a carbonyl compound and hydrocyanic acid is carried out in accordance with the method described above. | 09-13-2012 |
20140135521 | METHOD FOR PRODUCING ALPHA-HYDROXYCARBOXYLIC ACID ESTERS - The present invention relates to a continuous process for preparing alpha-hydroxycarboxylic esters by reacting at least one alpha-hydroxycarboxamide present in the liquid phase with an alcohol in the presence of a catalyst, which is characterized in that the resulting alpha-hydroxycarboxylic ester is at least partly separated from the reaction mixture via the gas phase. | 05-15-2014 |
20140187817 | PREPARATION OF METHACRYLIC ACID - The invention relates to a process for preparation of methacrylic acid, comprising process steps a) providing a crude methacrylic acid-comprising aqueous solution comprising at least one impurity at least partially dissolved therein; b) precipitation of at least a part of the at least one impurity from the crude methacrylic acid-comprising aqueous solution to form at least one solid impurity and a mother liquor; c) separation of at least a part of the at least one solid impurity from the mother liquor to obtain a purified methacrylic acid-comprising aqueous solution and a solid impurity; d) separation of methacrylic acid from the purified methacrylic acid-comprising aqueous solution. | 07-03-2014 |
20160068464 | METHOD FOR PRODUCING METHYLMETHACRYLATE - The present invention relates to a process for producing methyl methacrylate, comprising the following steps:
| 03-10-2016 |
20160090344 | METHOD FOR DEHYDRATING ALPHA-SUBSTITUTED CARBOXYLIC ACIDS - The present invention describes a process for preparing alpha-beta-unsaturated carboxylic acids by dehydration of hydroxycarboxylic or alkoxycarboxylic acids which are substituted in the alpha position, in particular 2-hydroxyisobutyric acid, while avoiding accumulation of by-products and additives. | 03-31-2016 |
20160137583 | METHOD FOR PRODUCING ALPHA-HYDROXYCARBOXYLIC ACID ESTERS - The present invention relates to a process for the production of alpha-hydroxycarboxylic esters by means of alcoholysis of the corresponding alpha-hydroxycarboxamide under heterogeneous catalysis. | 05-19-2016 |