The effect of enzyme concentration and space time on the performance of a continuous recycle membrane reactor for one-step starch hydrolysis

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Kinetics of continuous starch hydrolysis in a membrane reactor

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Supercritical fluid extraction of vetiver roots: A study of SFE kinetics

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The volatile oils from the Vetiveria zizanioides oil are particularly appreciated in perfume and cosmetic products but may also be used in the food industry as aroma and flavor agent. The objective of this work was to study the improvement over the conventional process on the quantity and quality of vetiver extracts recovered by supercritical technology (SFE). The pressure effect (100-300 bar) at 40 degrees C, and the influence of amount of ethanol used as cosolvent (0, 5 and 10%, v/v) were studied. Supercritical extraction process was compared to the hydrodistillation, based on vetiver extract quantity and quality; SFE extracts and presented khusimol contents of 14-29% over hydrodistillation and for SFE, the global yields and kinetic parameters obtained using 10% (v/v) of ethanol were statistically different from extraction using 0 and 5% of ethanol. The TLC and GC showed similar chemical profiles for SFE and HID, but were aware some compounds that were observed by TLC just during the t(CER) region. Mathematical modeling was performed for vetiver kinetics obtained by SFE + cosolvent and Sovova model showed the best adjusts for all curves. (C) 2008 Elsevier B.V. All rights reserved.472200208Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)CAPES [424/03]CNPq [472512/2004-8

Membrane contactor with hydrophobic metallic membranes: 2. Study of operating parameters in membrane evaporation

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A new reactor design combining enzyme, membrane and SC CO2: application to castor oil modification

International audienceThis study deals with the enzymatic modification of vegetable oils with the help of a newreactor design. Basically, the newreactor is a porous membrane contactor along and through which substrates are flowing. It is constituted from an enzymatic membrane and uses supercritical carbon dioxide (SC CO2) to fluidify the highly viscous substrates. The interesterification between castor oil triglycerides and methyl oleate catalysed by a lipase was chosen as a model reaction. It was preliminary tested and characterized in a batch reactor. Then the feasibility of the new process was demonstrated on a cross-flow filtration unit operating under SC CO2 conditions. The stability of the immobilized enzymes was checked and the influence of the transmembrane pressure on the reaction rate was observed

A new way to conduct enzymatic synthesis in an active membrane using ionic liquids as catalyst support

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