Polymeric Networks Derived from UV-Curing of Bio-Based Polyesters for Methyl Violet Removal

In this study, firstly, the syntheses and characterizations of biobased polyesters with different acid values obtained from the condensation reaction of biobased itaconic acid and polyethylene glycol were investigated. Then, UV curing was applied to form polymeric networks as adsorbent material from these polyesters containing different acids. Fourier transform infrared spectrometry (FTIR), Nuclear Magnetic Resonance Spectroscopy (NMR), X-ray Photoelectron Spectroscopy (XPS), Gel Permeation Chromatography (GPC) and scanning electron microscope (SEM) were used for the characterization of polymeric networks. The effects of the parameters of contact time, initial dye concentration, pH, temperature, amount of adsorbent on adsorption were investigated by batch method. In addition, adsorption equilibrium data were analyzed by Langmuir, Freundlich, Tempkin, Elovich, Redlich-Peterson, Harkin-Jura and Jossens adsorption models. Kinetic and thermodynamic studies were performed at 298, 308, 318 and 328 K and desorption studies were also examined. Comparison studies for the effects of the acid values of the adsorbent materials on the removal of methyl violet (MV) organic pollutant from aqueous solutions were analyzed. According to the pseudo-second-order model, the adsorption capacities were found to be ≥ 357.14 mg/g for the adsorbents. From the thermodynamic data, it was determined that the mechanism was exothermic and spontaneous. As a result of the third reuse, it was found that the adsorbents had a removal efficiency of ≥ 72.36%. According to the results observed the increase in the acidities in the chemical structure of bio-based polymeric networks enhances the adsoption properties.