Removal of Pb(II), Cd(II) and Zn(II) ions using a new poly(1,3-cyclohexylene oxalate) polymer

المجلة: Research Journal of Chemistry and Environment

سنة النشر: 2017

تاريخ النشر: 2017-07-07

Abstract A new polyoxalate polymer was synthesized by polycondensation of 1.3-cyclohexandiol and oxalyl chloride in dry chloroform at 0-5°C. The polymer was characterized by inherent viscosity, FT-IR. 'H-NMR. OC-NMR, thermal analysis and SEM. The removal characteristics of the polymer towards Pb(II), Cd(II) and Zn(II) tons were studied by batch equilibrium technique as a function of pH, temperature, metal concentration and contact time and as well as by column technique. The isothermal characteristics, thermodynamics and kinetics data of the metal ions anto the polymer were also investigated. Langmuir, Freundlich and Dubinin-Radushkevich (D- R) adsorption models were applied to describe the experimental data. The polymer showed high metal ion uptake towards Pb(II) and Zn(II), but lower uptake one toward Cd(II). However, the polymer was found to selectively adsorb Pb(II) and Zn(II) in the concentration variation isotherm experiments. The metal-loaded polymer was regenerated by 0.10 M HNO, which is more efficient than 0.10 M EDTA.

Synthesis and Characterization of Chelating Hyperbranched Polyester Nanoparticles for Cd(II) Ion Removal from Water

المجلة: Molecules

سنة النشر: 2022

تاريخ النشر: 2022-06-07

Abstract: Chelating hyperbranched polyester (CHPE) nanoparticles have become an attractive new material family for developing high-capacity nanoscale chelating agents with highly branched structures and many functional groups in the main chains and end groups that can be used to remove heavy metals from water. In this study, a hyperbranched polyester with a particle size of 180-643 nim was synthesized with A+B interfacial polymerization, using dimethylmalonyl chloride as the difunctional monomer (A) and 1,1,1-tris(4-hydroxyphenyl)ethane (THPE) as the trifunctional monomer (B). FTIR and NMR were used to characterize the CHPE and confirm the structure. The CHPE nanoparticles were generally considered hydrophilic, with an observed swelling capacity of 160.70%. The thermal properties of the CHPE nanoparticles were studied by thermal gravimetric analysis (TGA) with 1% mass loss at temperatures above 185 °C. The XRD of the CHPE nanoparticles showed a semi-crystalline pattern, as evident from the presence of peaks at positions-18° and 20 The nature of the surface of the CHPE was examined using SEM. Batch equilibrium was used to investigate the removal properties of the CHPE nanoparticles towards Cd(II) ions as a function of temperature, contact time, and Cd(II) concentration. The Cd(II) ion thermodynamics, kinetics, and desorption data on the CHPE nanoparticles were also studied.