Influence of Temperature and Pressure on the Evaporation of 6-Aminopenicillinic Acid

Abstract

6-aminopenicillinic acid (6-APA) is the raw materials for producing semi-synthetic penicillin. In commercial scale, penicillin G is conversed into 6-APA enzymatically by penicillin acylase. Due to the nature of equilibrium reaction, the products are in mixture solution of penicillin G, 6-APA, and phenil acetic acid (PAA). In order to purify the targetted 6-APA, steps of evaporation, crystallisation, and drying are thereby compulsory. In this research, the optimum operation conditions for model solution evaporation were observed. Operation variables, like temperature was varied in the range between 30-65°C at -100mmHg, and pressure was also set between -300 and -50mmHg at constant temperature of 50°C. The results showed that temperature is a dominant factor determining the yield of 6-APA, compared to vacuum pressure from -300 mmHg to -50 mmHg that provided similar yield value. This fact was supported by interpretation of the crystal’s purity for the pressure variation that overall was more than 90% (suggested the homogeneity and higher 6-APA content); hence, operation in each pressure for that range is feasible. To conclude, at 50°C and evaporation pressure of -100mmHg, the highest 6-APA yield and total yield of 97.46% and 91.76%, respectively, were attained.