Continuous and Selective Separation of EGCG from Tea Polyphenols by Fractional Extraction: Experiment and Simulation

A new and efficient method was explored to continuously separate (-)-epigallocatechin-3-gallate (EGCG) from tea polyphenols (TPs) by fractional extraction in centrifugal contactor separators (CCSs). The effects of different organic solvents on distribution behavior of monomers of TPs were studied, and two green extraction systems were established without reactive extractant. Based on phase equilibrium and the law of conservation of mass, a fractional extraction model was developed to investigate the influence of the process parameters such as phase ratio and the number of stages on extraction efficiency. By simulation and optimization, optimal parameters can be obtained for the separation of EGCG. EGCG can be separated by batch and continuous separation. Excellent results can be achieved by the two methods with high purity, high yield, and large output. Compared to the batch method, the continuous separation is more suitable for production in an industrial scale due to low-cost and continuous separation. (c) 2018 American Institute of Chemical Engineers AIChE J, 65: 259-269, 2019