从发酵液中吸附提取柠檬酸的研究

本文选用吸附容量大的884(?)树脂,考察柠檬酸与草酸在该树脂上的竞争吸附。用微分床测定草酸存在下柠檬酸吸附和解吸过程的总传质系数。用显式差分法解以总传质系数表征的动力学过程数学模型。结果表明:草酸有较大的竞争吸附性,且因草酸存在,柠檬酸吸附过程的总传质系数比纯柠檬酸溶液的为小,解吸过程的总传质系数则比纯柠檬酸溶液的大。过程数学模型理论透过曲线与柠檬酸纯溶液,柠檬酸与草酸混合液及发酵液的实验值吻合良好。

The Study of Adsorption Separation of Citric Acid From Citric Acid Fermentrtion Liquid

In this paper,No.884 adsorption resin is used as an adsorbent.We investigate that the oxalic acid and the other impurities in the fermentation liquid effect on the kinetic of adsorption or desorption of citric acid.The affinity factor of oxalic acid is relatively greater than citric acid in this No.884 adsorption resin.The conentration of 2% oxalic acid in the pure citric acid aqueous solution is inves-tinted in the differential bed and the total mass transfer coefficients of citric acid in the adsorption and desorption stage has been deter-mined.The total mass transfer coefficients of mixed citric acid solution is less than the pure citric acid in the adsorption stage.In contrast,it is inverse in the desorption stage.The explicit difference method has been adopted to resolve the continuous partial differential equation in terms of the dynamics of the mass transfer equation.The calculated theoretical breakthrough curve agrees well with the curves of pure citric acid,mixed solution of citric acid and oxalic acid or fermentation aqueous solution.