缓冲盐溶液反萃分离红霉素A、C的研究

用NaH2PO4-Na2HPO4缓冲盐溶液反萃醋酸丁酯相中的红霉素,以纯化酯相中的红霉素A。分别考察了缓冲盐pH值、相比(体积比)、温度对红霉素A、C反萃取的影响。实验结果表明:随着pH值的增加,红霉素A的反萃率大大减少,红霉素C的反萃率先增加后减小,当pH=8时,酯相中红霉素A纯度最高且损失最低;随着相比(A/O)的增加,红霉素A、C的反萃率及酯相中的红霉素A纯化效果都略有提高,但综合考虑反萃剂用量和红霉素A损失,可知相比(A/O)为2∶1时较优;随着温度的增加,红霉素A、C的反萃率都大大减小,且酯相中的红霉素A纯度略有下降,但因红霉素A反萃损失较少,可考虑在328 K时,反萃2次,除去大量红霉素C的同时损失较少的红霉素A。

Separation of erythromycin A and erythromycin C by reverse extraction of buffer solution

In order to purify the erythromycin A in butyl acetate,NaH2PO4-Na2HPO4 buffer solution was used to extract the erythromycin C from butyl acetate phase.The effects of the pH value of buffer solution,the phase volume ratio and temperature on the reverse extraction of erythromycin C and erythromycin A were determined.The results show that with the increase of the pH value,the reverse extraction ratio of erythromycin A decreases greatly,while that of erythromycin C increases firstly and then decreases.When pH=8,erythromycin A in butyl acetate phase has the highest purity and the least loss.With the increase of phase volume ratio(A/O),the reverse extraction ratios of both erythromycin A and erythromycin C and the purity of erythromycin A in butyl acetate all increase slightly.Considering the consumption of reverse extraction solvent and the loss of erythromycin A comprehensively,the phase volume ratio(A/O) of 2 ∶ 1 is suitable.With the increase of temperature,the reverse extraction ratios of both erythromycin A and erythromycin C decrease greatly,and the purity of erythromycin A in butyl acetate declines slightly.Extracting twice at 328 K can remove a large amount of erythromycin C and lose a smaller amount of erythromycin A.