Synthesis and Characterisation of Graphene Oxide-Silica-Chitosan for Eliminating the Pb(II) from Aqueous Solution

Abstract

Heavy metal ions have a toxic and negative influences on the environment and human health even at low concentrations and need to be removed from wastewater. Chitosan and graphene oxide are suitable nano plate adsorbents with high adsorption potential because of their π-π interaction, and they are available functional groups that interact with other elements. In this study, graphene oxide was coated with silica to enhance the hydrophilicity of the adsorbent. Subsequently, the adsorbent was functionalised by various amounts of chitosan to improve the Pb(II) removal. The adsorbent was analysed using transmission electron microscopy (TEM), Raman, Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), and mapping analysis techniques. An investigation of the influences of the initial concentration of Pb(II), pH and contact time were included to obtain the optimum amount of adsorption. The range of the initial Pb(II) concentration studied was from 10 to 120 mg/L. The pH factor ranged from 3 to 8 with contact time from 0 to 140 min. Freundlich, Temkin and Langmuir isotherm models were fit to the results, and a pseudo-second-order kinetic model was found to provide a good fit as well. The maximum Pb(II) removal capacity achieved was 256.41 (+/− 4%) mg/g based on Langmuir isotherms.

Biocompatibility and Angiogenic Effect of Chitosan/Graphene Oxide Hydrogel Scaffolds on EPCs

“…The porosity test simply confirms that the introduction of GO increases the porosity of the CS hydrogel scaffold. Furthermore, a better porosity can promote cell spreading and facilitate cell proliferation [ 47 , 48 ]. In addition, SEM images show that the introduction of GO makes the structure of the CS hydrogel scaffold more uniform, reduces the pore size, and increases the porosity.…”

Recent Developments in Chitosan-Based Adsorbents for the Removal of Pollutants from Aqueous Environments

“…A number of other additives has been combined with CS/GO, such as kaolin as a filler to enhance the mechanical strength of the hydrogel composite [ 220 ], lignosulfonate for additional binding sites [ 221 , 222 ], triethylenetetramine providing amine groups to enhance adsorption [ 223 ], hydroxyapatite to enhance strength and adsorption capacity [ 224 ] and silica as it contains a number of silanol groups (Si–OH) [ 225 ] and it can be furthermore employed to aid the dispersion of GO within chitosan to give effective adsorbents [ 226 ]. Moreover, other biopolymers have been combined with chitosan to form blends which are then combined with GO to give high performing adsorbents.…”

Electrospun Functional Nanofiber Membrane for Antibiotic Removal in Water: Review

“…Many kinds of pollutants, such as colored dyes [ 3 , 4 , 5 ], heavy metal ions [ 6 , 7 , 8 ], harmful bacteria [ 9 , 10 , 11 ] and drugs [ 12 , 13 , 14 ], are harmful to water. Among them, antibiotics have attracted attention as a new water pollutant [ 15 , 16 ].…”