Please use this identifier to cite or link to this item:
Author(s): Ricardo Couto
Pedro Vidinha
Célia Peres
Adriano S. Ribeiro
Olga Ferreira
Manuela V. Oliveira
Eugénia A. Macedo
José M. Loureiro
Susana Barreiros
Title: Geranyl acetate synthesis in a packed-bed reactor catalyzed by novozym in supercritical carbon dioxide and in supercritical ethane
Issue Date: 2011
Abstract: The esterification reaction of geraniol with acetic acid (100 mM/100 mM) catalyzed by immobilized Candidaantarctica lipase B (Novozym 435) was studied in supercritical carbon dioxide (sc-CO2) and in sc-ethane in a packed-bed reactor(PBR). In sc-CO2 it was easy to adjust the water activity (aw) in the reaction mixture to levels leading to good enzyme performance.Enzyme stability was high and steady-state conversions could be achieved that exceeded the largest conversions measured in batchstirred-tank reactors (BSTRs), which is probably due to the lower aw levels achieved in the PBR. In sc-ethane, where the solubility ofwater is lower, high steady-state conversions could be attained only by preventing the accumulation on the enzyme bed of the waterproduced during reaction. The kinetic parameters for the reaction in sc-CO2 were determined using previously published dataobtained in a BSTR, and a model was developed for the PBR that included those kinetic parameters. This model was able to predictwith reasonable accuracy the behavior of the PBR. Slight differences were observed for some operating regions, probably due to theinfluence of aw in the activity of the enzyme, which is not included in the model.
Subject: Ciências Tecnológicas, Engenharia química
Technological sciences, Chemical engineering
Scientific areas: Ciências da engenharia e tecnologias::Engenharia química
Engineering and technology::Chemical engineering
Related Information: info:eu-repo/grantAgreement/FCT - Fundação para a Ciência e Tecnologia/Programa de Financiamento Plurianual de Unidades de I&D/PEst-C/EQB/LA0020/2011/Projeto Estratégico-LA 20 - 2011-2012/LA 20
info:eu-repo/grantAgreement/FCT - Fundação para a Ciência e Tecnologia/Projectos de I&DT em Todos os Domínios Científicos/POCI/EQU/56732/2004/Síntese de acetato de decilo por catálise enzimática em meio supercrítico/POCI/EQU/56732/2004
Document Type: Artigo em Revista Científica Internacional
Rights: restrictedAccess
Appears in Collections:FEUP - Artigo em Revista Científica Internacional

Files in This Item:
File Description SizeFormat 
  Restricted Access
1.75 MBAdobe PDF    Request a copy from the Author(s)

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.