关键词: macrolide antibiotics;erythromycin;neutral complex extraction;synergistic extraction

Abstract: Based on the theory of reactive extraction, new solvent systems were developed to replace
butylacetate for extraction of macrolide antibiotics (erythromycin, kitasamycin, spiramycin
meleumycin etc.). A new neutral complex solvent extraction system, fatty alcohol-kerosene
(marked by E1), was used for extraction of erythromycin, one of the macrolide antibiotics.
The extraction equilibrium equation is obtained, and the extraction distribution is as
follows The effects of several parameters on extraction equilibrium were investigated.
Furthermore, a new synergistic extraction system (marked by E2) was developed, in which
another solvent was used as synergistic agent to replace the diluent kerosene in the
neutral complex extraction system. Based on these new extraction systems, an improved
process for extraction of erythromycin was developed, showing remarkable advantages in
technology and economics owing to its low solvent consumption of 3kg per billion unit
compared with 9－10 for butylacetate. The recovery process of solvent from raffinate may be
eliminated.

Key words: macrolide antibiotics, erythromycin, neutral complex extraction, synergistic extraction