Modelling and experimental studies on lipase-catalyzed isoamyl acetate synthesis in a microreactor

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• 作者：Polona Ž ; nidarš ; ič ; -Plazl ; Igor Plazl
• 关键词：Isoamyl acetate ; Esterification ; Microreactor ; Candida antarctica lipase B ; Mathematical modelling ; Two-phase system
• 刊名：Process Biochemistry
• 出版年：2009
• 出版时间：October 2009
• 年：2009
• 卷：44
• 期：10
• 页码：1115-1121
• 全文大小：385 K

文摘

A lipase-catalyzed synthesis of isoamyl acetate was studied in a continuously operated pressure-driven microreactor. The esterification of isoamyl alcohol and acetic acid occurred at the interface between n-hexane and an aqueous phase with dissolved lipase B from Candida antarctica. By adjusting flow rates of both phases, a parallel laminar flow with liquid–liquid boundary in the middle of the microchannel could be reestablished and a separation of phases was achieved at the y-shaped exit of the microreactor. Since product remained in the organic phase, this also enabled its continuous separation from the aqueous phase with the enzyme. A three-dimensional mathematical model was developed, considering the velocity profile developed for steady-state conditions between two immiscible fluids. The model contained convection, diffusion, and enzyme reaction terms, where esterification rate was described with a Ping-Pong Bi-Bi mechanism and inhibition by both substrates. Experimental data, which were in good agreement with model simulations, have demonstrated 35 % conversion at residence time 36.5 s at 45 °C and at 0.5 M acetic acid and isoamyl alcohol inlet concentrations, which is much faster as in any literature reported so far. According to model simulations, obtained by non-equidistant finite differences numerical solutions of complex non-linear equations system, further microreactor design and process optimization are feasible.