Countercurrent Chromatography Separation Process Theory Research And Applications

In 1970s, a new tecnology, named as counter-current chromatography (CCC), is developed for separation process. With the centrifugal force field, provided by rotation, the immiscible phases are mixed and settled in high frequency, and a series mixing and settling zones obtained. Then the substances, with different partition coefficients, will be separated and purified in CCC separation process. There are many advantages in CCC comparing with the ordinary chromatography technology, especially for the properties of "no substances losing" in CCC. Recently, the technology has been wildly used in the separation process, especially for the separation and purification of natural products.In the thesis, the theory for the mechanism, hydrodynamics and thermodynamics of solvents in CCC are introdued in detail. A new model, called theory of counter current extraction table (TCCET) model, are developed for the investigation of CCC separation process. With the model, the concentration in the column is characterized as binomial distribution and the concentration in out-flow is a negative binomial distribution. The separation process in CCC are analyzed in detail with the stastical and probility character of concentration equation, and the agreement between simulation and experiment results are quiet satisfactory. The TCCET model shows a linear additive property, and the soultes, injected in different time or volume, can be tracked well. For the purpouse of industrilization, the effect of large volume injection are discussed. It is found that the efficiency of CCC is decreased with large injection volume, and it increased slowly with the theoretic stage increase. When the injection volume is up to a certain value (50%), the increase stage method for high efficency will fail, and the cost for the equipment increasing dramatically.In our experiments, a number of substance with different octanol-water partition coefficients are selected for the inverstigation of partition coefficient in various solvents system. The solubility parameter is introduced to describe the difference of the immiscible two phase. The correlation of solubility parameter and partition coefficient is found as quadratic polynomial, and all of correlation coefficients are large than 90%. With the correlation equation, the paritition coefficient of solute can be predicted and the selection of the solvents can be speeded-up.