Adsorption characteristics and behavior of a graphene oxide–Al₁₃ composite for cadmium ion removal from aqueous solutions

Abstract

Graphene oxide-Al 13 (GO-Al 13 ) composites were synthesized by a hydrolysis method on the basis of graphite oxide and were characterized by XRD, FT-IR and SEM. The adsorption of Cd 2+ onto the GO-Al 13 composite was investigated as a function of pH, temperature and adsorbent dose. Langmuir and Freundlich models were employed to describe the adsorption equilibrium. The adsorption kinetic was investigated by the pseudo-first-order, pseudo-second-order and the intraparticle diffusion models. The results showed that the GO-Al 13 composite has excellent adsorption capacity, and the Cd 2+ removal rate could reach 98.92% at the optimum conditions. The adsorption isotherm fitted the Langmuir model well and the adsorption process was found to fit the pseudo-second-order rate equation. Also, the thermodynamic parameters including free energy (DG . ), enthalpy (DH . ) and entropy (DS . ) of adsorption were calculated. These experimental data suggested that the adsorption of Cd 2+ on GO-Al 13 composite was an endothermic and spontaneous process.

Study of Graphene Oxide Structural Features for Catalytic, Antibacterial, Gas Sensing, and Metals Decontamination Environmental Applications

“…Polyhydroxyaluminum cation AlO 4 Al 12 (OH) 24 (H 2 O) 12 7+ with Al 13 is a widely applied material for water treatment purposes due to its remarkable scaffold, greater molecular weight, and intense positive charge . Therefore, Zhao et al fabricated a unique GO–Al 13 hybrid through a hydrolysis procedure and evaluated its adsorption ability using cadmium metal ion as a model contaminant . They noticed that the adsorption efficiency was increased by increasing the adsorbent because of the generation of more active sites for the adsorption of metal ion.…”

“…223 Therefore, Zhao et al fabricated a unique GO−Al 13 hybrid through a hydrolysis procedure and evaluated its adsorption ability using cadmium metal ion as a model contaminant. 224 They noticed that the adsorption efficiency was increased by increasing the adsorbent because of the generation of more active sites for the adsorption of metal ion. Likewise, the thermal stability, less toxicity, and strong ionic and coordinate affinity of zirconium metal cation fascinated the researchers to develop GO−zirconium phosphate (GO−ZrP) nanocomposite as an adsorbent to eradicate heavy metals.…”

Biofabrication of a novel bacteria/bacterial cellulose composite for improved adsorption capacity

“…6c reveals that the adsorption of Pb(II) is less prominent at lower pH for both BC adsorbents. This trend can be explained as follows: The large amount of protons (H + ) in the strong acidity medium may compete with Pb(II) for hydroxyl groups, in both materials [30]; on the other hand, protonation of amide groups reduces the ability for coordination of Pb(II) in the BA/BC sample, resulting in a lower adsorption at a lower pH [31].…”

Synthesis of magnetic iron oxide/graphene oxide nanocomposites for removal of cadmium ions from water

“…In recent years graphene has attracted great interest of researchers. Graphene has a two-dimensional structure consisting of sp 2 hybridized carbon atoms covalently bonded in a honeycomb or hexagonal lattice [4]. Due to its superior thermal, mechanical, electronic, and chemical properties, graphene can be applied to many fields such as electronics, energy, sensors, and environment treatment [5].…”