Synthesis, characterization and application of high adsorption performance of novel 1,4-polyketone

Abstract

This study aims to develop an alternating polyketone containing cationic groups in one and four alternating positions for increased functionality. A novel polyarylidene ketone was synthesized using simple condensation polymerization of terephthaldehyde and 2,5-hexane dione (PAK) The physicochemical properties of the resulting polymer were evaluated using Fourier-transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, UV-Visible absorbance, fluorescence, and SEM investigations. The findings show that the polymer is amorphous, has good thermal stability, and emits red light. It can also be used as a dye adsorbent in aqueous solutions, with high selectivity for the cationic dye methylene blue (MB). The adsorbent efficiency of PAK was measured as a function of pH, dosage, and initial dye concentration; the greatest dye removal of 96 % was obtained at pH 10, 50 mg dosage, and initial dye concentration of 20 ppm. Kinetics and isotherms were studied, showing that the pseudo-second-order model described kinetic data better than Freundlich and Langmuir and revealed a satisfactory chemisorption process. This study suggests that PAK can purify MB dyeing wastewater, remove Zn2+, Cu2+, Ni2+, Co2+, Cd2+, Fe3+ metal ions well, and is selective for Fe3+ and Cu2+; ion adsorption is chelating-based.

Computational Insights on the Chemical Reactivity of Functionalized and Crosslinked Polyketones to Cu2+ Ion for Wastewater Treatment

“…Therefore, our results suggest that the XLPKs involve strong electrostatic interactions with the copper ion by the -NH 2 and -C=O groups as the main adsorption mechanism. These results agree with experimental studies of the uptake of Cu 2+ ions in poly arylidene ketone [65] and sulfonated polyketone [66], which resulted in a strong chemical bond by electrostatic contact between the copper ions and the chelating functionalities of the polymers.…”

“…mechanism. These results agree with experimental studies of the uptake of Cu 2+ ions in poly arylidene ketone [65] and sulfonated polyketone [66], which resulted in a strong chemical bond by electrostatic contact between the copper ions and the chelating functionalities of the polymers. Furthermore, the short distances of the Cu 2+ ion with the nitrogen or oxygen atoms in the XLPKs (Cu 2+ -X (N or O): 1.88-2.06 Å) suggests chemisorption in all the cases.…”

“…Then, the adsorption mechanism of the XLPK-Cu(II) complexes is explained by the interplay between charge transfer, polarization, and electrostatics driving forces. The same behavior has been found in related literature [65,66,68] for other polymers, in which the Cu 2+ uptake in aqueous environment resulted in a strong chemical bond by electrostatic interactions with the chelating functionalities of the polymers with a contribution through van der Waals forces.…”