In this paper

the vacuum evaporative crystallization process of β lactam antimicrobial pharmaceuticals is studied.The crystallization thermodynamic data

such as the phase equilibrium diagram and the metastable zone of pencillin G potassium are determined.Furthermore

the crystallization kinetic parameters for penicillin G potassium salt in n-butanolwater solution are measured by using an unsteady method.Therefore

the optimal operating time table for the crystallization process is established.