title: Novel zwitterionic inorganic-organic hybrids: synthesis of hybrid adsorbents and their applications for Cu2+ removal.
abstract: A series of zwitterionic hybrid adsorbents were prepared via the ring-opening polymerization of pyromellitic acid dianhydride (PMDA) and N-[3-(trimethoxysilyl)propyl] ethylene diamine (TMSPEDA), and a subsequent zwitterionic process as well as sol-gel reaction. Their applications for Cu(2+) removal by adsorption were performed. FTIR spectra confirmed the step products. TGA revealed that the initial decomposition temperature (IDT) of these zwitterionic hybrid adsorbents could arrive at near 150°C. DSC showed that T(g) values decreased with an increase in PMDA content in the hybrid matrix. Ion-change capacity (IEC) revealed that the cation-exchange capacities (CIECs) and anion-exchange capacities (AIECs) of these hybrid adsorbents were within the range of 9.13-11.49 and 4.97-6.28 mmol g(-1), respectively. Meanwhile, the CIECs and AIECs exhibit an opposite change trend as PMDA content increases. Adsorption experiment indicated that their adsorptions for Cu(2+) ions followed Lagergren second-order kinetic model, surface adsorption and intraparticle diffusion mechanisms might be the major process. These findings demonstrated that they are promising absorbents for the separation and recovery of Cu(2+) ions from contaminated water.
authors.affiliation: Key Laboratory of Membrane Materials & Processes, Department of Chemical and Materials Engineering, Hefei University, 373 Huangshan Road, Hefei, 230022, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Dong
authors.forename: Junsheng
authors.initials: J
authors.lastname: Liu
authors.forename: Long
authors.initials: L
authors.lastname: Song
authors.forename: Guoquan
authors.initials: G
authors.lastname: Shao
mesh_terms: D000327:Adsorption; D000465:Algorithms; D001565:Benzoates; D002152:Calorimetry, Differential Scanning; D003300:Copper / Q000302:isolation & purification*; D004058:Diffusion; D006868:Hydrolysis; D007202:Indicators and Reagents; D007287:Inorganic Chemicals / Q000737:chemistry*; D007474:Ion Exchange; D007700:Kinetics; D009930:Organic Chemicals / Q000737:chemistry*; D012826:Silicone Elastomers; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D013818:Thermogravimetry
chemical_list: D001565:Benzoates; D007202:Indicators and Reagents; D007287:Inorganic Chemicals; D009930:Organic Chemicals; D012826:Silicone Elastomers; C006194:aminoethyl-aminopropyl-trimethoxysilane; C012019:pyromellitic dianhydride; D003300:Copper