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Decylacetate synthesis by enzyme catalysis in SC-CO2

The main purpose of this work was the study of long chain esters production, using decyl acetate as model compound, by enzymatic catalysis in supercritical media, with the aim of developing a sustainable, clean and efficient process as an alternative to the traditional chemical processes. The combination of a sustainable and clean technology, as biocatalysis, with a green/natural solvent, as supercritical CO2, ...

Decyl acetate synthesis by enzyme catalysis in sc-CO2

The synthesis of decyl acetate, from the transesterification of vinyl acetate with decanol, was studied in a high-pressure experimental set-up, equipped with a variable volume batch reactor, operating isothermally at 35 ºC and 100 bar, using CO2 in supercritical conditions as solvent, and Candida antarctica lipase B (CALB), immobilized on the macroporous resin Lewatit B (Novozym 435®), as catalyst. The enzymati...

Production of esters by biocatalysed transesterification in supercritical CO2 a...

The development of sustainable processes that use renewable raw materials and minimize chemical and energetic waste has attracted considerable attention and represents a great challenge to both academic researchers and industrial experts. The use of enzymes to catalyse chemical transformations can constitute a more sustainable alternative to some traditional chemical processes and more than 100 biotransformatio...

Effectiveness factor for immobilized biocatalysts: two substratestwo products r...

Immobilized enzymes are being increasingly used as biocatalysts in numerous processes to obtain high-value products for the pharmaceutical, flavour and fragrance industries (Gandhi et al., 2000). The major advantages of immobilization include the increase in enzyme stability, the possibility of enzyme reutilization and the easy separation of the biocatalysts from the reaction mixture. However, it is necessary t...

Chiral separation by SMB chromatography

The paper deals with chiral separation by simulated moving bed (SMB) chromatography. A model for the prediction of the cyclic steady-state performance of the SMB, based on the analogy with the true moving bed (TMB), is developed assuming multicomponent adsorption equilibria, axial dispersion flow and the linear driving force approximation to describe the intraparticle mass transfer rate. The simulation package ...

Enantioseparation by simulated moving bed chromatography: modeling, simulation ...

The paper deals with chiral separation by Simulated Moving Bed chromatography. A practical tool for choosing the better SMB operating conditions as a function of the feed flow rate is proposed. The operation of a pilot unit of SMB, Licosep 12-26 (Novasep, France), is carried out for the separation of bi-naphthol enantiomers. Experimental results and model predictions are compared in terms of process performance...

Modeling strategies for enantiomers separation by SMB chromatography

Modeling strategies for simulated moving bed adsorbers were studied to compare the simulated moving bed model (SMB) that considers the real shift of the injection and collection points to the true moving bed approach (TMB) that considers liquid and solid flow in opposite directions. The prediction of these two models is compared in terms of steady-state performance, steady-state internal concentration profiles,...

Separation of enantiomers of a chiral epoxide by simulated moving bed chromatog...

The paper deals with chiral separation by simulated moving bed (SMB) chromatography. The separation of chiral epoxide enantiomers in microcrystalline cellulose triacetate using methanol as eluent is considered as illustrative example. The use of microcrystalline cellulose triacetate for the chromatographic separation of enantiomers is first reviewed and a methodology for obtaining basic data (adsorption equilib...

Separation of enantiomers of a chiral epoxide by simulated moving bed chromatog...

Chiral separation by SMB chromatography