Separation of evodiamine and rutaecarpine with simulated moving bed chromatography

Using C18 as the stationary phase and methanol/water=70/30 (volume ratio) as the mobile phase, the three-zone simulated moving bed was used to separate two alkaloids, evodiamine and rutaecarpine. The isotherms of the two alkaloids were determined by frontal analysis, which can be described by linear isotherms with the Henry coefficients of 3.11 for evodiamine and 5.25 for rutaecarpine. The axial diffusion coefficient and mass-transfer coefficients of the two alkaloids were estimated by empirical equations. The operation conditions were designed by triangle theory and optimization method based on the mathematical model. Through optimization, the maximum feed flow rate was 0.55 ml∙min-1. The experimental purities of two products were both higher than 99%. By asynchronous switching, the feed flow rate was increased to 0.62 ml∙min-1 without additional investment and product purity loss. © 2021, Chemical Industry Press Co., Ltd. All right reserved.