Removal of toxic Cr(VI) from water by a novel magnetic chitosan/glyoxal/PVA hydrogel film

Abstract

A B S T R A C TCoprecipitation of FeCl 2 and FeCl 3 produced magnetic iron nanoparticles (Fe 3 O 4 NPs). The latter was dispersed in an acetic acid solution of chitosan (CS), and then cross-linked with glyoxal, followed by addition of polyvinyl alcohol (PVA). The resulting gel was neutralized with NaOH giving our novel Fe 3 O 4 NPs/CS/glyoxal/PVA hydrogel film. This film was used as an efficient and reusable adsorbent for the removal of toxic Cr(VI) from water, at a rather wide range of pH. The absorbent film was characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared, and energy dispersive X-ray. Langmuir isotherm model suggested maximum Cr(VI) adsorption occurring at room temperature. Kinetic studies suggested a pseudo-second-order model for the adsorption. Our Fe 3 O 4 NPs/CS/glyoxal/PVA hydrogel is hoped to serve as a promising Cr(VI) adsorbent in wastewater treatment technology.

Preparation and properties of crosslinked poly(vinyl alcohol)/nanofibrillated cellulose based biocomposite by subcritical water/CO2process

“…PVA based hydrogels find wide application in areas such as agriculture, filtration, biomedical, and so forth. [19][20][21][22][23][24] Addition of NFC as reinforcing filler with PVA while preparing hydrogel provides superior mechanical properties, which is beneficial for different applications. [25,26] In our previous work, new crosslinking method was introduced to prepare PVA hydrogel in subcritical water/CO 2 medium by using citric acid (CA) as crosslinker.…”

Glutathione-magnetite nanoparticles: synthesis and physical characterization for application as MRI contrast agent

“…Magnetic nanoparticles (NPs) have been widely investigated and utilized in the last decades [1][2][3][4], due to their different applications in different fields such as, biotechnology [5], catalysis [6], wastewater treatment [7], optoelectronic [8] and biomedicine [9,10]. Specifically, in the field of biomedicine, applications for protein immobilization [11], as hyperthermia agents for cancer therapy [12,13], for drug delivery [3], and as contrast agents for Magnetic Resonance Imaging (MRI) [14][15][16][17] has been proposed.…”