Oriented Membrane Processes for the Treatment of Wastewater from the Pharmaceutical Industry Loaded with Paracetamol Compound

Paracetamol remains the most frequently used analgesic, and consequently, it has often been detected in aquatic environments. The recovery and extraction of this compound from pharmaceutical liquid discharges, as an important active ingredient, is a beneficial operation for the modern industry. This study reports on the selective extraction of paracetamol from a liquid solution using two affinity polymer membrane types: Polymer Inclusion Membrane (PIM) and Grafted Polymer Membrane (GPM) with Gluconic acid (GA) as an extractive agent. After the characterization by SEM and FTIR techniques of the developed membranes, they were used to perform the extraction processes of paracetamol substrate with good results (J₀ = 35 g. m⁻².h⁻¹ and, D* = 42.81 10⁻⁷ (cm² s⁻¹)). Previously published kinetic and thermodynamic models were adopted to determine values of parameters: macroscopic, permeability (P), initial flux (J₀) for the membrane’s performance and microscopic association constant (K_ass), and apparent diffusion coefficient (D*) relating to interactions between substrate and extractive agent, necessary for the diffusion of Paracetamol through the membrane phase. Similarly, the temperature factor’s influence was examined and activation parameters were determined to explain the results and confirm the mechanism related to the used extraction processes.