Research On Recovered Solvents In Ampicillin Trihydrate

Acetone and methylene choride are widely applied as solvents in manufacturing of pharmaceuticals. A large quantity of the same solvents are also used in proudction of ampicillin trihydrate. To reduce the cost, methylene cholride and acetone are both recovered from the steps of dissolution of 6-APA, anhydridization, condensation and washing. Due to the equipment and technical limit, a certain specification of recovered solvent is declined compared with the fresh one. The dissertation mainly discusses the quality control, specification and time cycles of recovered solvents.Distillation of recovered solvent will impact the quality of product due to quality reduce. Therefore, a suitable specification is required to be established to guarantee the stable quality of product, which is by means of conrolling the production process and quality of recovered solvent. In this dissertation, waste solvent is proposed to be treated by alkaline to destroy the soluble antibiotics. Water could be removed by distillation method. Evaporation could use to remove the pigment and impurities. In this way, assay, impurity, water and color could reach a certain standard. The quality of recovered solvent could be recycled and comply with requirement to produce qualified ampicillin trihydrate.The manufacturing process of recovered solvent is determined. The corresponding specification is studied. At the same time, the different specification of solvent is studied for the impaction to ampicillin trihydrate. We also provide the data for recovery of solvents in ampicillin trihydrate. Detailed description is listed as below.1. Control top and bottom temperature of distillation tower(acetone) at 55.0~58.0℃ and 97.0~103.0℃ respectively;2. Control top and bottom temperature of distillation tower(methylene chloride) at39.0~41.0℃and 55.0~65.0℃respectively;By comparison of final ampicillin trihydrate, the specification of recovered solvents are established as below.1. Recovered acetone: Assay≥95.0%,Methylene chloride≤4.0%,Total otherimpurities≤1.0%,Water content≤2.0%,Color≤15#;2. Recovered Methylene chloride: Assay≥94.0%,Acetone≤4.0%,Total otherimpurities≤2.0%,Water content≤0.2%,Color≤15#By tracking trend of recovered solvent and correspongding ampicillin trihydrate, one year life-cycle of recovered solvent could be applied in the production of ampicillin trihydrate.