Encontrados 9 documentos, a visualizar página 1 de 1
Lipase-catalyzed synthesis of butyl butyrate by alcoholysis in an integrated li...
Paiva, Ana L.; Rossum, Diman van; Malcata, F. XavierThis paper reports experimental work pertaining to alcoholysis between butanol and ethyl butanoate, catalyzed by an immobilized lipase in a liquid-vapor system where chemical reaction and physical separation are simultaneously carried out. The processing setup was tested for various compositions of the starting feedstock and operated under reduced pressure. Samples were withdrawn both from the boiler and the co...
Kinetics of lipase-mediated synthesis of butyl butyrate in n-hexane
Paiva, Ana. L.; Rossum, Diman Van; Malcata, F. XavierThis paper reports experimental and modeling work concerning alcoholysis reactions between butanol and ethyl butanoate, catalyzed by Lipozymee in n-hexane, using a batch stirred system at 608C. Description of the reaction kinetics was based on a postulated multisubstrate Ping Pong Bi Bi mechanism, and appropriate rate expressions were derived for all components in the reaction medium. Simplified models were fit...
Kinetics and mechanisms of reactions catalyzed by immobilized lipases
Paiva, Ana L.; Balcão, Victor M.; Malcata, F. XThis review focuses on the kinetics of several modes of immobilization of lipases, on the mechanisms of reactions of activation of immobilized lipases, and on the kinetics and mechanisms of reactions catalyzed by immobilized lipases. A comprehensive overview of the state of the art pertaining to structural features of lipases is provided as an aid to understand immobilization, interfacial activation, and cataly...
Comparison of the performance of integrated and sequential reaction and separat...
Paiva, Ana L.; Malcata, F. XavierIntegration of reaction and separation has experienced fast progress in this decade because it provides a convenient way of alleviating kinetic and/or thermodynamic constraints usually present in the more traditional sequential con"guration (where reaction is followed by separation), which limit the extent of reaction and also the purity of the products obtained thereby. The aim of this work was to quantitative...
Integrated vs. sequential reaction and separation: contributions for a global a...
Paiva, Ana L.; Rossum, Diman van; Malcata, F. XavierIntegration of reaction and separation in one single step has often been claimed to provide enhanced processing and economic results when compared with the traditional configuration where a reaction unit is followed by a downstream separation unit, due to alleviation of kinetic and thermodynamic constraints. This paper quantitatively addresses the kinetic and thermodynamic improvements which can be brought abou...
Cascading reactor-separator sets reduces total processing time for low yield Mi...
Paiva, Ana L.; Rossum, Diman Van; Malcata, F. XavierIntegration of reaction with separation has often been claimed to provide enhanced processing due to alleviation of processing constraints which, like equilibrium limitation or product inhibition, are common in enzyme-catalyzed reactions. In this paper, a mathematical model is developed to assess the effect of cascading sets of enzyme reactors and physical separators (which, when the number of sets tends to inf...
Integration of reaction and separation with lipases: an overview
Paiva, Ana L.; Malcata, F. XavierIntegration of reaction and separation steps in processes involving lipases is currently undergoing fast progress because it provides a convenient way to alleviate limiting kinetic factors that are common in biological reactions, viz. decreased product inhibition, increased product solubility, shifted chemical equilibria, increased selectivity, and reduced number of downstream unit operations and process stream...
Bioreactors with immobilized lipases: state of the art
Balcão, Vitor M.; Paiva, Ana L.; Malcata, F. XavierThis review attempts to provide an updated compilation of studies reported in the literature pertaining to reactors containing lipases in immobilizedforms, in a way that helps the reader direct a bibliographic search and develop an integrated perspective of the subject. Highlights are given to industrial applications of lipases (including control and economic considerations), as well as to methods of immobiliza...
Process integration involving lipase-catalyzed ester synthesis reactions
Paiva, Ana L.; Malcata, F. XavierThe technical feasibility of integrating bioconversion (using a lipase from Mucor miehei immobilized by ion exchange onto a macroporous resin) and product recovery (via mass transfer towards liquid/vapor equilibrium) was experimentally verified for the production of ethyl acetate from acetic acid and ethanol at 30 and 40 °C. The configuration selected consisted of a packed bed thermostatted reactor inserted bet...
| Financiadores do RCAAP | |||||||
|
|
|
|
|
|
||