Outstanding Performance of a New Exfoliated Clay Impregnated with Rutile TiO2 Nanoparticles Composite for Dyes Adsorption: Experimental and Theoretical Studies

Abstract

Pure rutile TiO2 nanoparticles (Rt) were combined with exfoliated black clay (BC) to prepare a new composite for water decontamination, in particular, for the uptake of methylene blue (MB) and methyl orange (MO) dyes. The as-prepared Rt/BC was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and Field emission scanning electron microscopy (FESEM) techniques, and the dyes’ adsorption isotherms at three temperatures (i.e., 25, 40, and 50 °C) were studied. The results indicated that Rt/BC displayed a high removal performance for MO (96.7%) and MB (91.4%) at pH 3.0 and 8.0, respectively. Adsorption data of MB and MO were adjusted by a double layer model at all temperatures. The theoretical parameters of this statistical physics model were interpreted to understand the MO and MB adsorption mechanisms at the molecular level. The removed molecules per active site (n) of Rt/BC ranged from 1.12 to 1.29 for MB and 1.47 to 1.85 for MO, thus representing parallel orientation and multi-interactions mechanisms (i.e., van der Waals forces, hydrogen bonding, and electrostatic interactions were involved). The Rt/BC composite had a density of surface adsorption sites of 100 mg/g. The aggregation of MO molecules was high and increased their adsorption capacities (Qsat = 294–370 mg/g) compared to that of MB (Qsat = 214–249 mg/g). Adsorption energies were 9.70–20.15 kJ/mol, and these values indicated that MO and MB adsorption processes were endothermic and occurred via physical interactions. Overall, the low cost, high regeneration performance, and stability of Rt/BC support its application as a promising adsorbent for organic pollutants from wastewaters.

Fe3O4 Nanoparticles Loaded Bentonite/Sawdust Interface for the Removal of Methylene Blue: Insights into Adsorption Performance and Mechanism via Experiments and Theoretical Calculations

“…Then, the SD was dried at 65 • C/48 h and ground to pass through a 100µm mesh sieve. The bentonite sample was modified by H 2 O 2 using a previously described method [22] as follows: 3.0 g of the BE was added to a clean beaker with 25 mL of distilled water with stirring for 60 min. Then, 15 mL of H 2 O 2 was added to this BE/H 2 O mixture with continuous stirring for 2 h at 40 • C to produce BE with open pits and holes.…”

“…Graphene 153 [37] Kaolin 45 [38] Montmorillonite 64 [39] Chitosan/magnetic silica 201 [40] Zeolite 4A 22 [38] Polydopamine microspheres 90.7 [12] Activated rice husk 65 [41] Ball clay 25 [13] Fe 3 O 4 /montmorillonite 69 [42] Rt/BC 214.52 [22] Fibrous clay minerals 39-85 [43] Purified diatomite 105 [44] Fe 3 O 4 /serpentine composite 201 [21] Activated carbon 289.25 [45] BE/SD-MNPs composite 347.99 This study…”

“…Furthermore, this steric parameter can provide the effect of temperature on changing the adsorption mechanism. Overall, three probable cases can describe the MB adsorption orientation according to this parameter [2,5,17,22,45].…”

Characterization and Removal Efficiency Analysis of MWCNT/Clay Nanocomposites for MB Dye Adsorption

“…Among these methods, the adsorption technique has gained popularity for its cost-effectiveness, simple operation, environmental friendliness, and ability to work at ambient temperature and pressure. Organic dyes, in particular, must be removed from effluents, and to achieve this, various well-known adsorbents such as hydrogel, activated carbon, natural fibers, carbon nanotubes, zeolites, and polymer materials have been developed [6,[11][12][13][14][15]. The efficacy of adsorption as a vital decolonization method in dyeing wastewater treatment is recognized, with its reliance on kinetic and equilibrium measurements offering simplicity and cost savings [16].…”