Cr(VI) removal using Fe₂O₃-chitosan-cherry kernel shell pyrolytic charcoal composite beads

Abstract

In this study, cherry kernel shell pyrolytic charcoal was synthesized (CKSC) and composite beads were obtained by blending this pyrolytic charcoal with chitosan and Fe2O3 nanoparticles (Fe-C-CKSC). Cr(VI) adsorption from aqueous solutions by Fe-C-CKSC composite beads and CKSC adsorbents was studied comparatively. The effects of Cr(VI) initial concentration, adsorbent dosage, contact time, pH and temperature parameters on Cr(VI) adsorption were investigated. Adsorption reached an equilibrium point within 120 min for CKSC and Fe-C-CKSC adsorbents. The maximum Cr(VI) removal was obtained at the initial pH value of 1.56 for CKSC and 2.00 for Fe-C-CKSC. The optimum adsorbent dosage was found to be 5 g/L for CKSC and 3 g/L for Fe-C-CKSC. Based on the Langmuir model, the maximum adsorption capacities were calculated as 14.455 mg/g and 47.576 mg/g for CKSC and Fe-C-CKSC, respectively. Thermodynamic and kinetic studies were performed. As a result of adsorption kinetics calculations, adsorption was found to be consistent with the pseudo second order kinetic model. Characterization of the synthesized adsorbents was performed by SEM, BET, FTIR and elemental analysis. This study has shown that low cost adsorbents CKSC and Fe-C-CKSC can be used in Cr(VI) removal from aqueous solutions.

Role of nanohybrid NiO–Fe3O4 in enhancing the adsorptive performance of activated carbon synthesized from Yemeni-Khat leave in removal of Pb (II) and Hg (II) from aquatic systems

“…From the EDX data, the 0.2 KeV short signal is attributed to carbon [ [57] , [58] , [59] ], whereas the 0.60 KeV middle band is attributed to oxygen [ 58 ]. Iron is thought to be responsible for the bands that formed at 6.46 and 7.41 keV, while other signals that existed at 0.90, 7.50, and 8.20 keV are related to the presence of nickel [ [59] , [60] , [61] , [62] , [63] ]. These bands demonstrate that Ni–Fe oxides presented onto the surface of AC, supporting the successful formation of NF/AC nanocomposites.…”

Removal of Various Heavy Metals by Sewage Sludge Immobilized Onto Rod-type Chitosan Biosorbent

“…The spectra of the raw biosorbent and chitosan-immobilized biosorbents displayed many absorption peaks. A broad and strong band in the 3600-3200 cm −1 region was associated with N-H and O-H stretching vibrations in amine and hydroxyl groups [13]. Two spectra also displayed absorption peaks at 1650 cm −1 and 1750 cm −1 relevant to the stretching band of the carboxyl double bond in the carboxyl functional group [14].…”

Removal of Hexavalent Chromium(VI) from Wastewater Using Chitosan-Coated Iron Oxide Nanocomposite Membranes

“…Various types of adsorbents have been developed recently. For example, functionalized iron oxide nanoparticles (i.e., Fe 2 O 3 and Fe 3 O 4 ) have been widely used for efficient removal of toxic heavy metal ions due to their low toxicity, easy and inexpensive preparation, and large surface area [22][23][24][25]. However, their adsorption efficiency is not satisfactory due to the slow adsorption kinetics, and moreover an additional separation process for removal of the adsorbent from the water is required after the desalination procedure is finished.…”