Superparamagnetic Core-Shell Polymeric Nanocomposites for Efficient Removal of Methylene Blue from Aqueous Solutions

Abstract

Ultrafine well-dispersed Fe 3 O 4 magnetic nanoparticles (NPs) were directly prepared in an aqueous solution using controlled co-precipitation method. The Fe 3 O 4 -poly(acrylamide-co-sodium acrylate) core-shell magnetic nanogels are prepared by solution polymerization of acrylamide (AM) and sodium acrylate (AA-Na) monomers in the presence of Fe 3 O 4 NPs, N,N′-methylenebisacrylamide (MBA) as a cross-linker, N,N,N′,N′-tetramethylethylenediamine and potassium peroxydisulphate (KPS) as the redox initiator system. The novel Fe 3 O 4 -poly(acrylamide-cosodium acrylate) core-shell magnetic nanocomposite hydrogels are prepared by in situ free radical co-polymerization of AM and AA-Na in an aqueous dispersion of nanogel particles using MBA as the cross-linker and KPS as the initiator. The as-prepared nanocomposite hydrogels are characterized by Fourier transform infrared spectroscopy spectra, X-ray powder diffraction and transmission electron microscopic measurements. The mean particle size of the synthesized magnetite (Fe 3 O 4 ) NPs was approximately 8 nm. The diameter of the stabilized polymer-coated Fe 3 O 4 nanogels is approximately 11 nm. The surface morphology of the nanocomposites has been studied by scanning electron microscopy and atomic force microscopy. The Fe 3 O 4 -poly(acrylamide-co-sodium acrylate) nanocomposites have been extensively investigated for the removal of basic dyes from aqueous solutions. Results of batch experiments showed that these adsorbents exhibited high sorption capacities towards methylene blue (MB). Experimental data were analyzed using first-order kinetics, pseudo-second-order kinetics and intra-particle diffusion models. The kinetics followed a pseudo-second-order equation. Equilibrium isotherm data were analyzed according to Langmuir and Freundlich equations. The thermodynamic parameters for the adsorption of MB onto the nanocomposite hydrogels were also calculated. Regeneration of nanocomposite adsorbents can be easily achieved.

Reusable Superparamagnetic Raspberry‐Like Supraparticle Adsorbers as Instant Cleaning Agents for Ultrafast Dye Removal from Water

“…This is because these values also correspond well with the theoretical calculation for 60 wt% of spherical, 95 nm respectively 10 nm sized silica nanoparticles mixed with 40 wt% of spherical 10 nm sized iron oxide nanoparticles which results in a theoretical surface area of 62 m 2 /g and 182 m 2 /g, respectively. Compared to other adsorber systems reported in literature, the specific surface area is about average . Adsorbers with higher surface area such as 1380 m 2 /g and 2134 m 2 /g were reported as well ,.…”

“…Compared to other adsorber systems reported in literature, the specific surface area is about average. [15][16][17][18][19] Adsorbers with higher surface area such as 1380 m 2 /g and 2134 m 2 /g were reported as well. [6,5] Yet, the approach reported herein comes with all the flexibility to build a system of desired composition, e. g. in terms of silica nanoparticle amount and size and magnetic nanoparticle content, in a completely flexible, "Lego building block like" manner (compare Scheme 1).…”

Preparation of magnetite and silver poly(2‐acrylamido‐2‐methyl propane sulfonic acid‐co‐acrylamide) nanocomposites for adsorption and catalytic degradation of methylene blue water pollutant

“…There are some drawbacks for applying the nanomaterials as adsorbents due to their toxicity, bioactivity, recyclability and difficulties in collecting the nanomaterials and separating them from the treated water. These problems can be circumvented by using non‐toxic and magnetically smart nanocomposites by combining catalyzed or iron oxide materials with a crosslinked hydrophilic polymer . Moreover, nano‐hybrid magnetic materials have been subsequently used to adsorb water pollutants by magnetic separation or photocatalytic degradation of pollutants .…”

Synthesis, characterization and adsorption studies of an acrylic acid-grafted sodium alginate-based TiO2hydrogel nanocomposite

“…Among these techniques, adsorption has been found to be an economical, simple and efficient process for the removal of dyes in aqueous solution (Atta et al, 2013;Raizada et al, 2014;Walker et al, 2003). Synthetic and natural biopolymer-based adsorbents have been produced and used for the adsorption of dyes from aqueous solution (Prado et al, 2004;Xua et al, 2006).…”

“…A series of methods such as coagulation and flocculation, membrane separation, oxidation or ozonation, electro-coagulation and adsorption have been utilized for the removal of dyes from wastewater (Gimbert et al., 2008; Kim et al., 2005; Singh et al., 2013). Among these techniques, adsorption has been found to be an economical, simple and efficient process for the removal of dyes in aqueous solution (Atta et al., 2013; Raizada et al., 2014; Walker et al., 2003). Synthetic and natural biopolymer-based adsorbents have been produced and used for the adsorption of dyes from aqueous solution (Prado et al., 2004; Xua et al., 2006).…”