Magnetic removal of crystal violet from aqueous solutions using polysaccharide‐based magnetic nanocomposite hydrogels

Abstract

Magnetic Fe3O4@SiO2 starch‐graft‐poly(acrylic acid) (SPAA) nanocomposite hydrogels were prepared and used as absorbents for removal of crystal violet from aqueous solutions. Dynamic swelling, effect of contact time, absorption kinetics and nanocomposite hydrogel mass for removal of crystal violet dyes from aqueous solutions were studied. Fourier transform infrared spectroscopy, scanning electron microscopy and vibrating sample magnetometer measurements were used for the characterization of the nanocomposite hydrogels. The nanocomposite hydrogels had high magnetic sensitivity under an external magnetic field, which allowed their magnetic separation from water, thus avoiding secondary pollution. The results obtained are very promising since: (i) high levels of colour removal (>85%) were achieved with low magnetic SPAA nanocomposite mass and (ii) the magnetic SPAA nanocomposites can be successfully used several times as absorbents of crystal violet in aqueous solution without needing filtration. © 2012 Society of Chemical Industry

Magnetic hydrogel for better adsorption of heavy metals from aqueous solutions

“…31 Nanosized magnetic materials are recently developed and it has 32 applications in many fields including separation, drug delivery, 33 tissue engineering [11][12][13] etc. The magnetic materials with 34 modified surface functionalities are recently been developed for 35 removal of heavy metals and dyes from aqueous solution [14][15][16]. 36 Hydrogels, a three dimensional polymeric materials can be used as 37 a template for the synthesis of magnetic nano particles and 38 structures.…”

“…Cd reaches the water 13 bodies through paint, deterioration of galvanised pipes etc. 14 According to Indian standard specifications for drinking water 15 (IS:10500) and United State Environmental Protection Agency 16 (EPA) the desirable limit of Zn and Cd in drinking water is 5.0- 17 10.0 mg L À1 and 0.01 mg L À1 , respectively. The level of Zn beyond 18 5 mg L À1 can cause astringent taste, appear opalescent in water 19 and cause health problems such as stomach cramps, nausea and 20 pancreas damage if taken in excess.…”

“…Magnetic hydrogels are materials composed of 40 inorganic magnetic component in the form of particles, fibres or 41 lamelle of nanometer range embedded in an organic polymer. The 42 in situ prepared magnetic hydrogels have recently many applica- 43 tions especially in environmental and medical fields [15,12]. For its 44 environmental application the functional group in the hydrogel 45 having capacity to bind with organic and inorganic pollutants 46 could be utilised.…”

Green route for selective gram‐scale oxidation of sulfides using tungstate/triazine‐based ionic liquid immobilized on magnetic nanoparticles as a phase‐transfer heterogeneous catalyst

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Synthesis of magnetic carboxymethyl chitosan-g-poly(acrylamide)/laponite RD nanocomposites with enhanced dye adsorption capacity

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