微波辅助萃取柠檬皮中果胶动力学及热力学研究

Microwave-assisted Extraction Kinetics and Thermodynamics of Pectin from Lemon Peel

采用离子液体氯化1-丁基-3-甲基咪唑水溶液为萃取剂,对微波辅助萃取柠檬皮中果胶的动力学及热力学进行研究。以Fick扩散第二定律为理论基础,采用分离变量法建立果胶提取动力学方程,并推算出速率常数k、活化能Ea、焓变ΔH0、熵变ΔS0和自由能变ΔG0等动力学和热力学函数值。

The kinetic and thermodynamic mechanisms of the extraction process of pectin from lemon peel using 1-butyl-3-methylimidazolium chloride aqueous solution as extractant under microwave assistance were investigated.Based on the theory of Fick＇s second law,a dynamic model of pectin extraction was deduced by using the method of isolated variables and rate constant k,activation energy Ea,enthalpy change Δ H0,entropy change ΔS0 and free energy change ΔG0 were calculated.This model provides a valuable theory basis for the selection of optimum technological conditions for pectin extraction.