Polymeric hydrogels obtained using a redox initiator: Application in Cu(II) ions removal from aqueous solutions

Abstract

Poly(acrylic acid-co-acrylamide) hydrogels were prepared via free-radical solution polymerization, crosslinked with ethylene-glycol-dimethacrylate, potassium persulfate/ammonium bisulfite as the initiator, and applied in the removal of Cu(II) ions from aqueous solutions. Molar ratios of acrylamide/acrylic acid moieties and the amount of crosslinking agent were varied to determine the swelling capacities of hydrogels and maximum metal uptake. Polymerization kinetics was investigated by 1 H-NMR. Hydrogel physicochemical properties were characterized by nitrogen sorption measurements, elemental analysis, FTIR, and X-ray photoelectron spectroscopy (XPS). Swelling results indicated that hydrogels were swollen up to 27,500%. Hydrogels showed equilibrium Cu(II) adsorption capacities of 211.7 mg g 21 and fast kinetics ($20 min). Langmuir isotherm fitted adsorption equilibrium data. FTIR and XPS results helped in elucidating the presence of monodentate copper complex on the surface of hydrogels. A simple synthesis route of hydrogels using the redox initiator suggests the potential application in the removal of toxic metals from aqueous streams. V C 2013Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39933.

Synthesis of polymer-surfactants by gamma irradiation for removal nickel ions from aqueous solution

“…Different weights of surfactants (3) (0.01, 0.02, 0.03, 0.04, 0.05, 0.0005 g) were added to mixture of 60 ml of acrylamide (AAm) which equal 42.6 g, 60 ml of acrylic acid (AAc) and 80 ml of distillated water, each mixture was stirred for two hrs, then the resulted mixtures were polymerized by using Gamma irradiation at 25 KGy [27][28][29]…”

“…Repeat the previous procedure at different weights of surfactant (4) (0.01, 0.02, 0.03, 0.04, 0.05, 0.00141 g) [27][28][29].…”

“…The mixture was stirred at the different time intervals. Then, the concentration of residual nickel ion was determined by EDTA at the end of each time [27][28][29].…”

Redox two-component initiated free radical and cationic polymerizations: Concepts, reactions and applications

“…On the contrary, choosing specific acrylamides can lead to interesting gel polymerizations initiated by ascorbic acid/ferrous sulfate/ammonium persulfate in the literature [265]. Hydrogels are also accessible via redox polymerization [266][267][268][269][270][271]. In the case of a redox polymerization under the mild conditions defined above, strong limitations could be identified for the efficient commercially available RFRP initiating systems: 1) Toxicity/instability/hazard of some of the oxidizing agents (e.g.…”

Implementation of Carboxymethyl cellulose/Acrylic acid/ Titanium dioxide Nanocomposite Hydrogel in Remediation of Cd(II), Zn(II) and Pb(II) for Water treatment application

“…Super absorbing poly(acrylic acid-coacrylamide) hydrogels were synthesized by redox initiator and used for removal of Cu(II) ions from aqueous solutions [18]. Carboxylate grafted cellulose densified with TiO2 was developed for extraction of uranium (VI) from aqueous solutions [19].Chitosan-g-poly(acrylic acid) hydrogels were prepared from an aqueous dispersion polymerization method and used for removal of Ni(II) [20].…”