Patent application number | Description | Published |
20120035396 | PROCESS FOR PREPARING MDA VIA THE STAGE OF THE AMINAL - The invention relates to a process for preparing methylenediphenyldiamine (MDA), comprising the following steps a) to c):
| 02-09-2012 |
20120046497 | METHOD FOR PRODUCING COLOR-STABLE MDA AND MDI - The invention relates to a process for preparing methylenediphenyldiamine (MDA) by reacting formaldehyde and aniline in the presence of an acidic catalyst, wherein the oxygen content in the process for preparing MDA is <10 000 ppm, based on all compounds present in the process. | 02-23-2012 |
20120087855 | PROCESS FOR THE OXIDATION OF HYDROGEN CHLORIDE OVER A CATALYST HAVING A LOW SURFACE ROUGHNESS - The invention relates to a process for the catalytic oxidation of hydrogen chloride by means of oxygen to form chlorine in a fluidized-bed process in the presence of a catalyst comprising ruthenium on a particulate support composed of alpha-aluminum oxide having an average particle size of from 10 to 200 μm, wherein the catalyst support has a low surface roughness and can be obtained from a used catalyst which has been used in a fluidized-bed process for at least 500 hours of operation. | 04-12-2012 |
20120108844 | METHOD OF MEASURING ENTRY OF WATER INTO PHOSGENE-CONDUCTING PLANTS - The invention relates to a method of measuring entry of water and resulting corrosion in plants for producing isocyanates by reacting phosgene with one or more primary amines in a solvent. The invention further relates to an apparatus for producing such isocyanates, in the work-up section of which probes for monitoring corrosion are arranged in defined places. | 05-03-2012 |
20120123151 | PROCESS FOR PREPARING METHYLENEDI(PHENYL ISOCYANATE) - The invention relates to a process for preparing methylenedi(phenyl isocyanate), which comprises (a) the phosgenation of two-ring and/or multiring methylenedi(phenylamine), (b) the fractionation of the crude methylenedi(phenyl isocyanate) obtained to give two-ring and multiring isomers, (c) the purification and/or fractionation of the resulting mixture of two-ring isomers of methylenedi(phenyl isocyanate) and (d) the storage of the mixtures obtained in step (c) or in step (b), wherein part of the stored mixtures is reused by means of recirculation in at least one of steps (b) or (c). | 05-17-2012 |
20120123153 | METHOD FOR PURIFYING MIXTURES COMPRISING 4,4'-METHYLENEDIPHENYL DIISOCYANATE - The invention relates to a method for purifying mixtures comprising 4,4′-methylenediphenyl diisocyanate, which comprises purifying by distillation a mixture I comprising 4,4′-methylene-diphenyl diisocyanate by means of a column K1, wherein the gaseous stream comprising the mixture I is brought into contact in the column K1 with at least one liquid compound A which has the same or higher boiling point than 4,4′-methylenediphenyl diisocyanate, and wherein the gaseous stream O obtained at the top of the column and comprising 4,4′-methylenediphenyl diisocyanate is cooled in a maximum of 5 seconds to a temperature of 20° C. to 60° C. | 05-17-2012 |
20120142960 | METHOD FOR PURIFYING MIXTURES COMPRISING 4,4'-METHYLENEDIPHENYL DIISOCYANATE - The invention relates to a method for purifying mixtures comprising 4,4′-methylenediphenyl diisocyanate, which comprises purifying by distillation a mixture I comprising 4,4′-methylenediphenyl diisocyanate having a hydrolyzable chlorine content as specified in ASTM D4663-10 of greater than 100 ppm by means of a column K | 06-07-2012 |
20130240779 | METHOD OF REGULATING THE VISCOSITY OF A MIXTURE COMPRISING AT LEAST TWO COMPONENTS HAVING DIFFERENT VISCOSITIES - The invention relates to a method of regulating the viscosity of a mixture ( | 09-19-2013 |