Parameters and mechanism of membrane-oriented processes for the facilitated extraction and recovery of norfloxacin active compound.

In the present work, a polymer inclusion membrane (PIM) using an amphiphilic molecule Tween 20 (TW20) as the carrier was developed and characterized to hinder environmental contamination caused by norfloxacin (NRF), an antibiotic widely used in veterinary and human medicines. Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) coupled with energy X-ray dispersion spectroscopy (EDS) were used to reveal the composition, porosity, and morphology of the elaborated membrane. In order to measure the performance of the as-developed membrane, the influences of NRF initial concentration (C0 = 0.04 mol L-1, 0.02 mol L-1, 0.01 mol L-1, and 0.005 mol L-1), pH (2.6, 4.5, and 10.5), and temperature (T = 298 K, 303 K, and 305 K) were investigated. The evolution of macroscopic (permeability (P) and initial flux (J0)), microscopic (association constant (Kass) and apparent diffusion coefficient (D*)), and activation parameters (activation energy (Ea), enthalpy (∆H≠ass), and entropy (∆S≠)) was analyzed. It was found that TW20 was an effective agent for the extraction and recovery of different forms of NRF, especially the zwitterion form appeared at pH = 4.5. On the other hand, for the biologically active NRF compound, the mechanisms of the studied processes were controlled by the kinetic aspect rather than the energetic counterpart. Graphical abstract.