Simulation, Synthesis and Characterization of a Smart Polymer for Selective Adsorption of Acid Red 114 Dye from Aqueous Solutions

Abstract The textile industry, despite its economic importance, significantly contributes to environmental pollution, particularly by contaminating water resources, disrupting ecosystems. This study introduces an alternative method for removing the dye C.I. Acid Red 114 using molecularly imprinted polymers (MIP), a selective and smart material. Density Functional Theory (DFT) insights revealed that the interaction of C.I. Acid Red 114 with acrylamide occurs primarily by the oxygen from SO 3 - groups and hydrogen from NH 2 , which is favored by protonation, as occurs on harsh aqueous environments such as textile wastewater. Several factors influencing dye removal were investigated, including pH, concentration, contact time, and adsorbent mass. A non-imprinted polymer (NIP) was synthesized as a control to assess MIP efficiency. Both polymers were characterized and tested to evaluate MIP performance as a potential solution for pollutant removal in the textile industry. The dye exhibited a linear detection range of 2 to 12 mg·L -1 , with a detection limit of 0.60 mg·L -1 . Adsorption tests demonstrated that the MIP outperformed the NIP, following a first-order kinetic model. The Freundlich model best described the adsorption process (AICc = 3.492). Additionally, the MIP showed approximately 80% selectivity for C.I. Acid Red 114, confirming its effectiveness as an adsorbent for textile wastewater treatment. MIP recovery rates ranged from 91.2% to 97.5% in HPLC analysis of three different river water samples.