Abstract: Process for isolating pure 1,3-butadiene from a crude C4 fraction by extractive distillation using a selective solvent, wherein (a) the crude C4 fraction is introduced into a predistillation column, a first low boiler fraction comprising C3-hydrocarbons is taken off as overhead stream, a gaseous C4 fraction is taken off as side stream and a first high boiler fraction is taken off as bottom stream, (b) the gaseous C4 fraction is brought into contact with a selective solvent in at least one extraction column, giving an overhead fraction comprising butanes and butenes and a bottom fraction comprising 1,3-butadiene and selective solvent, (c) crude 1,3-butadiene is desorbed from the bottom fraction in at least one stripping column, with a stripped selective solvent being obtained and the stripped selective solvent being recirculated to the extraction column, and (d) at least part of the crude 1-3-butadiene is fed to a pure distillation column and a second high boiler fraction is separated off and a gaseous purge s

Abstract: A process comprising hydrothermally synthesizing a titanium-containing zeolitic material having framework type MWW in the presence of an MWW template compound, obtaining a mother liquor comprising water, a first portion of the MWW template compound and a titanium-containing zeolitic material having framework type MWW comprising a second portion of the MWW template compound, separating the first portion of the MWW template compound from the mother liquor and recycling the first portion of the MWW template compound into a hydrothermal synthesis of a titanium-containing zeolitic material having framework type MWW.

Abstract: Process for isolating pure 1,3-butadiene from a crude C4 fraction by extractive distillation using a selective solvent, wherein (a) the crude C4 fraction is introduced into a predistillation column, a first low boiler fraction comprising C3-hydrocarbons is taken off as overhead stream, a gaseous C4 fraction is taken off as side stream and a first high boiler fraction is taken off as bottom stream, (b) the gaseous C4 fraction is brought into contact with a selective solvent in at least one extraction column, giving an overhead fraction comprising butanes and butenes and a bottom fraction comprising 1,3-butadiene and selective solvent, (c) crude 1,3-butadiene is desorbed from the bottom fraction in at least one stripping column, with a stripped selective solvent being obtained and the stripped selective solvent being recirculated to the extraction column, and (d) at least part of the crude 1-3-butadiene is fed to a pure distillation column and a second high boiler fraction is separated off and a gaseous purge s

Abstract: A distillation device comprising a column for separating a feed stream into a head product stream, a bottom product stream and optionally one or more side extraction streams, having three or more cells in 5 series through which fluid flows, wherein at least the first cell is integrated into the bottom of the column, for multi-stage heating and partial evaporation of the liquid flowing through the cells with the exception of the liquid from the last cell in an evaporation stage.

Abstract: A process comprising hydrothermally synthesizing a titanium-containing zeolitic material having framework type MWW in the presence of an MWW template compound, obtaining a mother liquor comprising water, a first portion of the MWW template compound and a titanium-containing zeolitic material having framework type MWW comprising a second portion of the MWW template compound, separating the first portion of the MWW template compound from the mother liquor and recycling the first portion of the MWW template compound into a hydrothermal synthesis of a titanium-containing zeolitic material having framework type MWW.

Abstract: A process for preparing trans-enriched MDACH, including: distilling an MDACH starting mixture in the presence of an auxiliary, which is an organic compound having a molar mass of 62 to 500 g/mol, a boiling point at least 5° C. above the boiling point of cis,cis-2,6-diamino-1-methylcyclohexane, and 2 to 4 functional groups, each of which is independently an alcohol group or a primary, secondary or tertiary amino group. The MDACH starting mixture includes 0 to 100% by weight of 2,4-MDACH and 0 to 100% by weight of 2,6-MDACH, based on the total amount of MDACH present in the MDACH starting mixture. The MDACH starting mixture includes both trans and cis isomers. Trans-enriched MDACH includes 0 to 100% by weight of 2,4-MDACH and 0 to 100% by weight of 2,6-MDACH, where the proportion of trans isomers in the mixture is higher than the proportion of trans isomers in the MDACH starting mixture.

Abstract: A method for isomerizing a starting mixture comprising 2,4-diamino-1-methylcyclohexane, 2,4-MDACH for short, 2,6-diamino-1-methylcyclohexane, 2,6-MDACH for short, or mixtures thereof, wherein the isomerization is carried out in the presence of a supported catalyst with zirconium dioxide as support and ruthenium as active metal.

Abstract: A distillation device comprising a column for separating a feed stream into a head product stream, a bottom product stream and optionally one or more side extraction streams, having three or more cells in 5 series through which fluid flows, wherein at least the first cell is integrated into the bottom of the column, for multi-stage heating and partial evaporation of the liquid flowing through the cells with the exception of the liquid from the last cell in an evaporation stage.

Abstract: A method for isomerizing a starting mixture comprising 2,4-diamino-1-methylcyclohexane, 2,4-MDACH for short, 2,6-diamino-1-methylcyclohexane, 2,6-MDACH for short, or mixtures thereof, wherein the isomerization is carried out in the presence of a supported catalyst with zirconium dioxide as support and ruthenium as active metal.

Abstract: A process for preparing trans-enriched MDACH, including: distilling an MDACH starting mixture in the presence of an auxiliary, which is an organic compound having a molar mass of 62 to 500 g/mol, a boiling point at least 5° C. above the boiling point of cis,cis-2,6-diamino-1-methylcyclohexane, and 2 to 4 functional groups, each of which is independently an alcohol group or a primary, secondary or tertiary amino group. The MDACH starting mixture includes 0 to 100% by weight of 2,4-MDACH and 0 to 100% by weight of 2,6-MDACH, based on the total amount of MDACH present in the MDACH starting mixture. The MDACH starting mixture includes both trans and cis isomers. Trans-enriched MDACH includes 0 to 100% by weight of 2,4-MDACH and 0 to 100% by weight of 2,6-MDACH, where the proportion of trans isomers in the mixture is higher than the proportion of trans isomers in the MDACH starting mixture.