| The low level of separation technology led to a slow development of traditional Chinese medicine (TCM) modernization. The new NF membrane technology has its quality and environmental benefits superiority over traditional separation technology. Thus, the development of membrane materials with high flux and rejection and function at lower pressures are of great interest. In this paper, CA NF membrane was prepared from CA/solvent or CA/solvent/non-solvent system for separation of baicalin from radix scutellariae raw extracts.First, for each CA/THF, CA/AC, CA/DIO system with different CA content, water flux and rejection of PEG400 were compared, the zero shear viscosities were obtained by falling ball viscometer, and effect of the exposed time to air on membrane behavior were compared.To gain stable behavior, non-solvent was added into CA/solvent system. The max water content for each binary system was tested by cloud point tirration, and the factors-water content and different exposed time-were investigated. The membranes surface and cross structures were taken by SEM.By intrinsic viscosity tests, the effects of solvent and non-solvent on dilute CA solution behavior were reflected. It was found that the properties of dilute solution affect the membrane performance. For binary system, the opposite relationship between viscosity slope coefficients (b) and water flux (J) were due to solvent kind. For CA/solvent/non-solvent ternary system, [η] increased when 0< Φ_ 2<0-15, due to cooperative effect.The process (water extraction-centrifugal-UF-NF) was designed for separation bacailin, which made good separation results.
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