Abstract: The present invention relates to a continuous process for obtaining 2-ethylhexyl acrylate (2-EHA) from a mixture (1) that is liquid under an absolute pressure in the range from 0.5 to 100 bar and has a temperature in the range from 0 to 300° C., comprising 2-EHA, at least one high boiler, at least one homogeneous catalyst, and at least one low boiler, wherein the mixture (1) is depressurized by a pressure-maintenance device (3) to an absolute pressure level in the range from 0.1 to 10 bar, wherein the resulting two-phase gas/liquid mixture (16) is continuously supplied to a helical-tube evaporator (4) in which, at a temperature in the range from 50 to 300° C., the 2-EHA content of the liquid phase of the two-phase gas/liquid mixture is reduced by partial evaporation, this being accompanied by a parallel increase in the 2-EHA content of the gas phase of the two-phase gas/liquid mixture, and the two phases are discharged in the form of a resulting two-phase gas/liquid output stream (17).

Abstract: The invention relates to an apparatus for carrying out mass transfer processes, comprising a column having at least two inlet pipes for introducing a gaseous phase, where separation-active internals are accommodated in the column and a column section extends from the at least two inlet pipes to the separation-active internals, in which section a coverage of a cross-sectional area of the column is less than 25%, based on the total cross-sectional area, and where the at least two inlet pipes have a height offset which corresponds to not more than three times an inlet pipe diameter and the at least two inlet pipes are at an angle (?) of from 60° to 150° to one another and have asymmetry with respect to one another. The invention further relates to a use of the apparatus and also a method for designing the apparatus.

Abstract: Process for the removal of volatile compounds from a tackifier comprising a resin with repeating units of formula I wherein R1 is a linear or branched alkylen group with 1 to 10 carbon atoms and R2 is a linear or branched, saturated or unsaturated N aliphatic hydrocarbon group with up to 20 carbon atoms, and optionally a plasticizer, wherein the tackifier is passed through at least one evaporator as film and the volatile compounds are removed from the film.

Abstract: Process for isolating pure cyclohexyl (meth)acrylate from a mixture comprising cyclohexyl (meth)acrylate, cyclohexanol and entrainer, by feeding or introducing the mixture is fed as side feed stream into a rectification column having a bottom vaporizer, separation-active internals and a stripping section and an enrichment section, where the column has from 4 to 50 theoretical plates, the side feed stream is introduced in the region commencing at least one theoretical plate above the bottommost theoretical plate and ending at least one theoretical plate below the uppermost theoretical plate, the pressure at the top of the column is in the range from 10 mbar to 5 bar and the reflux ratio is from 1:0.2 to 1:10, and the bottom output is fed to a further distillation unit in which the cyclohexyl (meth)acrylate is separated off at the top or at a side offtake.

Abstract: Process for the removal of volatile compounds from a tackifier comprising a resin with repeating units of formula I wherein R1 is a linear or branched alkylen group with 1 to 10 carbon atoms and R2 is a linear or branched, saturated or unsaturated N aliphatic hydrocarbon group with up to 20 carbon atoms, and optionally a plasticizer, wherein the tackifier is passed through at least one evaporator as film and the volatile compounds are removed from the film.

Abstract: A process for continuously preparing a butyl acrylate H2C?CH—C(?O)OR, with R=n-butyl or isobutyl, wherein aqueous 3-hydroxypropionic acid is converted under dehydrating and esterifying conditions in the presence of the corresponding butanol R—OH in a reactor with a rectification column and butyl acrylate formed, unconverted butanol and water used and formed are distilled off overhead as a ternary azeotrope, after separation into a liquid aqueous phase and liquid organic phase each of the aqueous and organic phases is at least partly discharged, and the organic phase comprising the butyl acrylate and the butanol is subjected to distillative separation.

Abstract: A process for isolating pure butyl acrylate from crude butyl acrylate, which is carried out in a dividing wall column having separation-active internals and a vaporizer, and in which: a dividing wall is arranged in a longitudinal direction of the column to form an upper joint column region, a lower joint column region, an inflow section having a side feed point and an offtake section having a side offtake point; a ratio of an amount of liquid at an upper end of the dividing wall going to an enrichment section and a stripping section of the column is set in the range from 1:0.2 to 1:5; and a ratio of an amount of vapor streams at a lower end of the dividing wall going to the stripping section and the enrichment section of the column is set in a range from 1:0.5 to 1:2.0.

Abstract: Process for isolating pure 2-ethylhexyl acrylate or pure 2-propylheptyl acrylate from the corresponding crude alkyl acrylate by distillation, wherein the process is carried out in a dividing wall column (1) which has separation-active internals and vaporizer (7) and in which a dividing wall (8) is arranged in the longitudinal direction of the column to form an upper joint column region (9), a lower joint column region (14), an inflow section (10, 12) having a side feed point (2) and an offtake section (11, 13) having a side offtake point (3), the column has a number of theoretical plates in the range from 10 to 60, where the number of theoretical plates of the dividing wall column (1) relates to the sum of the theoretical plates in the joint upper column region (9), the joint lower column region (14) and the inflow section (10, 12), the side feed point (2) for the corresponding crude alkyl acrylate is arranged at a theoretical plate in the region commencing at least two theoretical plates above the bottommost

Abstract: A process for isolating pure tert-butyl (meth)acrylate from crude tert-butyl (meth)acrylate by distillation, wherein the process is carried out in a dividing wall column having separation-active internals and a vaporizer and in which a dividing wall is arranged in the longitudinal direction of the column to form an upper joint column region, a lower joint column region, an inflow section having a side feed point, and an offtake section having a side offtake point, where the column has from 20-80 theoretical plates and the ratio of the amount of liquid at the upper end of the dividing wall going to the enrichment section and the stripping section of the column is set in the range from 1:0.2 to 1:5.

Abstract: A process for continuously preparing a butyl acrylate H2C?CH—C(?O)OR, with R=n-butyl or isobutyl, wherein aqueous 3-hydroxypropionic acid is converted under dehydrating and esterifying conditions in the presence of the corresponding butanol R—OH in a reactor with a rectification column and butyl acrylate formed, unconverted butanol and water used and formed are distilled off overhead as a ternary azeotrope, after separation into a liquid aqueous phase and liquid organic phase each of the aqueous and organic phases is at least partly discharged, and the organic phase comprising the butyl acrylate and the butanol is subjected to distillative separation.

Abstract: Process for isolating pure 2-ethylhexyl acrylate or pure 2-propylheptyl acrylate from the corresponding crude alkyl acrylate by distillation, wherein the process is carried out in a dividing wall column (1) which has separation-active internals and vaporizer (7) and in which a dividing wall (8) is arranged in the longitudinal direction of the column to form an upper joint column region (9), a lower joint column region (14), an inflow section (10, 12) having a side feed point (2) and an offtake section (11, 13) having a side offtake point (3), the column has a number of theoretical plates in the range from 10 to 60, where the number of theoretical plates of the dividing wall column (1) relates to the sum of the theoretical plates in the joint upper column region (9), the joint lower column region (14) and the inflow section (10, 12), the side feed point (2) for the corresponding crude alkyl acrylate is arranged at a theoretical plate in the region commencing at least two theoretical plates above the bottommost

Abstract: A process for isolating pure butyl acrylate from crude butyl acrylate, which is carried out in a dividing wall column having separation-active internals and a vaporizer, and in which: a dividing wall is arranged in a longitudinal direction of the column to form an upper joint column region, a lower joint column region, an inflow section having a side feed point and an offtake section having a side offtake point; a ratio of an amount of liquid at an upper end of the dividing wall going to an enrichment section and a stripping section of the column is set in the range from 1:0.2 to 1:5; and a ratio of an amount of vapor streams at a lower end of the dividing wall going to the stripping section and the enrichment section of the column is set in a range from 1:0.5 to 1:2.0.

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: Process for isolating pure tert-butyl (meth)acrylate from crude tert-butyl (meth)acrylate by distillation, wherein the process is carried out in a dividing wall column (1) which has separation-active internals and vaporizer (7) and in which a dividing wall (8) is arranged in the longitudinal direction of the column to form an upper joint column region (9), a lower joint column region (14), an inflow section (10, 12) having a side feed point (2) and an offtake section (11, 13) having a side offtake point (3), the column has a number of theoretical plates in the range from 20 to 80, where the number of theoretical plates of the dividing wall column (1) relates to the sum of the theoretical plates in the joint upper column region (9), the joint lower column region (14) and the inflow section (10, 12), the side feed point (2) for the crude tert-butyl (meth)acrylate is arranged at a theoretical plate in the region commencing at least two theoretical plates above the bottommost theoretical plate and ending at least

Abstract: The invention relates to a process for dehydrating aqueous 3-hydroxypropionic acid to acrylic acid in the liquid phase, wherein aqueous acrylic acid is removed continuously from the liquid phase and the aqueous 3-hydroxypropionic acid and/or the liquid phase have a high content of oligomeric 3-hydroxypropionic acid.

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: The invention relates to a process for dehydrating aqueous 3-hydroxypropionic acid to acrylic acid, wherein an aqueous mixture of 3-hydroxypropionic acid and oligomeric 3-hydroxypropionic acid is converted to acrylic acid in the liquid phase in a first step and aqueous acrylic acid is distilled out of the liquid phase, and the aqueous acrylic acid is separated by distillation into an acrylic acid-rich phase and a water-rich phase in a second step.

Abstract: The invention relates to a process for dehydrating aqueous 3-hydroxypropionic acid to acrylic acid in the liquid phase, wherein aqueous acrylic acid is removed continuously from the liquid phase and the liquid phase comprises an inert organic solvent 1.

Abstract: The invention relates to a process for dehydrating aqueous 3-hydroxypropionic acid to acrylic acid, wherein an aqueous mixture of 3-hydroxypropionic acid and oligomeric 3-hydroxypropionic acid is converted to acrylic acid in the liquid phase in a first step and aqueous acrylic acid is distilled out of the liquid phase, and the aqueous acrylic acid is separated by distillation into an acrylic acid-rich phase and a water-rich phase in a second step.

Abstract: The invention relates to a process for dehydrating aqueous 3-hydroxypropionic acid to acrylic acid in the liquid phase, wherein aqueous acrylic acid is removed continuously from the liquid phase and the liquid phase comprises an inert organic solvent 1.