Ferrocene–Functionalized Carbon Nanotubes: An Adsorbent for Rhodamine B

Abstract

It is well-known that direct discharges of dye-contaminated wastewaters generated from various industries (i.e., textile, cosmetics and food industries,…) cause severe effects on both aquatic environment and human health. Decontamination of dye-containing wastewaters using nanomaterials-based adsorbents such as carbon nanotubes is regarded as an interesting field of investigation to control these types of pollutants. In this context, a newly prepared ferrocene-modified carbon nanotubes (amFc-MWCNTs) was applied as an adsorbent for the removal of rhodamine B (RhB) dye from aqueous solutions. The structural properties of the hybrid adsorbent were fully characterized using Raman, XPS, EDX, SEM and TEM microscopy. Adsorption isotherms and kinetics of RhB were investigated and multiple models (i.e. Langmuir, Freundlich, Hill,…) were used to fit experimental data. It was found that > 98% of RhB with initial concentration of 10 mg L −1 can be captured within 2 h when using 0.4 g L −1 of amFc-MWCNTs. The adsorption behavior of this nanomaterial fitted well with the Hill isotherm and the pseudo-second-order kinetic model. Moreover, the intra-particle diffusion was identified as the rate-limiting step of the adsorption process. After washing with acetone, regenerated amFc-MWCNTs adsorbent showed good recovery, indicating its reusability and its potential in practical applications.

Adsorption Behaviour of Rhodamine B on Hen Feather and Corn Starch Functionalized with Green Synthesized Silver Nanoparticles (AgNPs) Mediated with Cocoa Pods Extracts

“…The maximum monolayer adsorption (q max ) capacities calculated for adsorbents ranging from feather-AgNPs > starch-AgNPs > feather > starch are 56.53, 48.60, 4.27 and 1.176 mg g −1 respectively. This reveals that functionalization with AgNPs greatly improved the adsorption performances of starch and feather which is agreement with FTIR, SEM and XRD results that rougher and more porous surfaces have higher adsorptive characteristics [5,24,27]. The improvements in adsorption capacity of functionalized feather and functionalized starch are 30 and 40 folds better than raw feather and starch respectively.…”

“…6. The surface charges and binding sites on adsorbents, degree of ionization and mobility of adsorbates are significantly influenced by pH [3][4][5][6]. Maximum uptake of Rh-B was obtained for starch (63.4%) at pH 6.02, starch-AgNPs (64.7%) at pH 6.78, feather (68.7%) at pH 2.11 and feather-AgNPs (70.8%) at pH 2.04.…”

“…Rh-B has been reported to irritate the skin, eyes, respiratory tracts, induce hormonal disturbances in addition to being neurotoxic and genotoxic. Also, it readily undergoes anaerobic degradation in water producing carcinogenic amines from reductive amination and remediation using conventional and biological methods has not yielded great results due to its complex structure, toxicity and high molecular weight [5][6][7][8][9][10][11][12].…”

“…Adsorption provides one of the best ways of dye removal and as such has been applied for Rh-B uptake with different adsorbents such silver nanoparticle from cobweb [3], activated carbon [4], ferrocene-functionalized carbon nanotubes [5], acid and alkaline-functionalized Musa paradisiaca biochar [6], nanocomposite hydrogel [7], animal bone meal [8], exhausted coffee ground [9], gelatin/activated carbon composite beads [10], Fe/ZnO-shell shrimp nanocomposite [11], polar-functionalized post-cross-linked resins [12], calcined egg shell [13], seeds of Aleurites moluccana [14], zinc oxide loaded activated carbon [15] and anodic porous alumina in sodium dodecyl sulphate solution [16] amongst other methods. Although, excellent adsorptions of Rh-B have been achieved with these adsorbents, drawbacks from their applications relating to limited abundance, low adsorption capacity, lack of reproducibility, renewability, biodegradability in addition to expensiveness and probable secondary pollution which could create distress in the environment required the use of biodegradable bio-composite which are abundantly available.…”

Hydrothermal Synthesis and Characterization of K7V5W8O40·12H2O: Application to Rhodamine B Removal by Adsorption/Photocatalysis

“…By contrast, the physical methods are practical and the adsorption has already given satisfactory results for cleaning the contaminated effluents. During the last decades, a series of natural adsorbents, including activated carbon [21,22], clay [23], zeolites [24], montmorillonite [25], alginate [26], bentonite [27] and dolomite [28] have been developed to eliminate dyes from water but present some disadvantages. Thus, the research turned to synthetic adsorbents, and the polyoxometallates have received a growing attention not only because of their potential applications in the of catalysis [29][30][31][32] and magnetism [33], but also for their fascinating architectures, including chiral structures [34], penetrating frameworks [35], electronic [36,37], biological chemistry [38,39], photocatalysis [40][41][42], adsorbents [43], medicine [44] and biocatalysis [45].…”