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该文采用纳滤分离低浓度乙醇中绿原酸,探索道南效应和溶解-扩散效应对绿原酸分离的影响规律。实验表明溶液pH、乙醇浓度影响绿原酸分离行为,30%乙醇中绿原酸pH 3~7,截留率相差70.27%,通过响应面法建立二次回归模型,纳滤膜截留相对分子质量、溶液pH、乙醇浓度存在交互作用,绿原酸存在状态决定了其分离行为,随着乙醇浓度的增加,游离态绿原酸因溶解-扩散效应易吸附溶解在膜表面而促进其透过,解离态绿原酸在道南效应和溶解-扩散效应的双重作用下,难以进入膜表面,而截留率显著升高。优选出的纳滤富集工艺相较于传统减压浓缩优势明显,解决了中药分离精制过程中,低浓度有机试剂环境中中药成分在溶剂回收时存在效率低下、成分损失严重的技术难题。
In this paper, nanofiltration was used to separate chlorogenic acid in low concentration ethanol to explore the effect of Thana and Dissolution-Diffusion on chlorogenic acid separation. The experimental results showed that the pH and ethanol concentration of the solution affected the chlorogenic acid separation behavior. The chlorogenic acid in 30% ethanol had a pH of 3 ~ 7, the retention rate was 70.27%. The second regression model was established by response surface methodology. The interaction between solution pH and ethanol concentration existed. The existence of chlorogenic acid determined its separation behavior. With the increase of ethanol concentration, the free-form chlorogenic acid was easily dissolved and dissolved on the membrane surface due to the dissolution-diffusion effect to promote its permeation and dissociation Under the double action of channel effect and dissolution - diffusion effect, the state chlorogenic acid is hard to enter the membrane surface and the rejection rate is significantly increased. The nanofiltration enrichment process is obviously superior to the traditional vacuum concentration process, which solves the technical problem that the traditional Chinese medicine composition has low efficiency and serious loss of components in the process of solvent recovery in the process of separation and purification of traditional Chinese medicine.