A study of synergetic carrier emulsion liquid membrane for the extraction of amoxicillin from aqueous phase using response surface methodology

Abstract Amoxicillin (AMX) is the most commonly used antibiotic in life. AMX was extracted from aqueous solution by synergetic carrier emulsion liquid membrane (ELM) technology for the first time. The membrane phase of ELM was mainly composed of kerosene and butyl acetate. The carrier has consisted of Aliquat-336 and TOA, the surfactant was Span-80, and the membrane enhancer was liquid paraffin. And Na2CO3 and NaCl were used as the internal aqueous phase for extraction. Firstly, the basic structure and mechanism of emulsion were characterized and analyzed. And then, the center composite design (CCD) of response surface methodology (RSM) was used to optimize the operating conditions. The optimal values were: Aliquat-336 concentration (1.1% v/v), trioctylamine (TOA) concentration (8.6% v/v), and extraction time (15 min), AMX concentration (75 mg/L). A polynomial model was fitted to predict the extraction yield of AMX. Under the optimal operating conditions, the optimal extraction prediction value was 98.58%, the extraction actual value was 98.2%, and the recovery rate of AMX was 75.3%.