Settings

Now showing1 - 5 of 5
  • Some of the metrics are blocked by your 
    consent settings
    Item type:Publication, Access status: without files ,
    Enzyme Reactors and Process Control
    (Springer, 2024-03-22)
    Ohde, Daniel
    ;
    Kühn, Steffen
    ;
    Liese, Andreas
    Publicationtype: Book Part
      12
  • Some of the metrics are blocked by your 
    consent settings
    Item type:Publication, Access status: with files ,
    Reaction engineering in biocatalytic reactive distillation
    (2018)
    Kühn, Steffen
    ;
    Liese, Andreas
    Reactive distillation is a well-established unit operation in chemical industry incorporating reaction and separation in one device. In this study, practicability of Candida antarctica lipase B is evaluated for biocatalytic kinetic resolution of either secondary alcohols or chiral esters to broaden the scope of feasible reactions in reactive distillation. In fact, successful operation of an integrated batch biocatalytic reactive distillation column is approved by in situ isolation of the chiral target compound (S)-2-pentanol with high purity (x = 0.95 mol/mol) and excellent enantiomeric excess (ee > 99 %). Finally, generated experimental data are used to propose an approach comprising criteria for selection of reaction candidates as well as the definition of an operation window.
    Publicationtype: Doctoral Thesis
      753  626
  • Some of the metrics are blocked by your 
    consent settings
    Item type:Publication, Access status: without files ,
    In situ separation of the chiral target compound (S)-2-pentanol in biocatalytic reactive distillation
    (American Chemical Society (ACS), 2017-06-07)
    Kühn, Steffen
    ;
    Sluyter, Gerrit
    ;
    Christlieb, Marc-Andreas
    ;
    Heils, Rene
    ;
    Stöbener, Anne-Kathrin Christine
    In situ separation of a chiral target compound is realized for the first time as distillate on top of an integrated biocatalytic batch reactive distillation column. The applied reaction system is the racemic resolution of (R/S)-2-pentanol in a transesterification with propyl butyrate, which is catalyzed by immobilized Candida antarctica lipase B (Novozym435). Biocatalyst integration is realized in baskets of wire gauze catalytic packings as column internals. The equilibrium limited reaction is shifted to the product side by fractional distillation of low boiling propanol and the target compound (S)-2-pentanol. Increased molar fractions up to x(S)-2-PeOH = 65 ± 4% with an enantiomeric excess of 90 ± 4% and 51 ± 3% overall conversion are reached for (S)-2-pentanol. Feasibility of the reaction system is investigated in our preselection tool. This tool is developed to evaluate predefined operation conditions in the column setup for transesterification reactions based on criteria regarding biocatalyst stability and boiling point differences between the reactants. The subsequently selected reaction of (R/S)-2-pentanol with propyl butyrate is successfully carried out in a batch reactive distillation column with in situ separation of our target compound (S)-2-pentanol. In contrast to current examples in the literature, this clearly demonstrates the possibility of one-pot target compound isolation within chiral synthesis applying biocatalytic reactive distillation.
    Publicationtype: Journal Article
      116
  • Some of the metrics are blocked by your 
    consent settings
    Item type:Publication, Access status: without files ,
      44
  • Some of the metrics are blocked by your 
    consent settings
    Item type:Publication, Access status: without files ,
      64