Fe–Ni Nanostructures and C/Fe–Ni Composites as Adsorbents for the Removal of a Textile Dye from Aqueous Solution

Abstract

Novel adsorption materials-Fe-Ni nanostructures and C/Fe-Ni composites-with the carbonaceous material coming from sewage sludge, have been developed and evaluated to remove indigo carmine from aqueous solution. The adsorbents were characterized by transmission and scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and BrunauerEmmett-Teller analysis. Sorption kinetics and isotherms were determined and the adsorption behaviours analysed. All adsorbents here studied have exhibited good efficiency to remove indigo carmine from aqueous solution. Pseudo-second-order kinetic and LangmuirFreundlich isotherm models were successfully applied to the experimental data. Fe-Ni nanostructures adsorption capacity was 977.18 mg/g, followed by C/Fe-Ni 75/25% composite with 654.33 mg/g, and a lowest value, 486.41 mg/g, was obtained for C/Fe-Ni 95/5% composite. It can be suggested that the sorption mechanism of the dye is chemisorption on these heterogeneous novel, cheap and efficient functional materials. All materials provide the highest adsorption capacities in pH between 4 and 10. In addition, three sorption-desorption cycles using 30% H 2 O 2 solution and distilled water were performed; sorption efficiencies of both composites (C/FeNi 75/25% and C/FeNi 95/5%) decreases in each cycle, but this behaviour is not observed for FeNi nanoscale oxides.

Novel tuffite/Fe-Cu oxides nanocomposite with functionality for dye removal in aqueous solution

“…3b). These results are consistent with those reported in works forming similar nanocomposites using different support materials [3,18]. These relatively small mean sizes of the thus obtained nanoparticles can be associated to the fast way of adding to the mixture solution of the reducing agent (NaBH 4 ), which causes the rapid reduction rate of both metal ions to form nanoparticles fixed on TUF mineral.…”

“…Therefore, the presence of nanostructures favored the removal process of MG dye. The use of Fe-Cu nanostructures supported on natural material or waste material has been reported for removal of azo dye [3]. However triphenylmethane dyes (MG) have not been studied that much with nanostructures adsorbents.…”

“…Recently, nanoparticles have been suggested as efficient, costeffective and environmental friendly alternative specifically metallic nanoparticles, which have relatively higher chemical activity and specificity of interaction [3]. In general, the nanoparticles work in two-fold ways: like adsorbent material and as reducing agent of organic compound, such as dyes.…”

“…The addition of other transition metal, such as copper, may enhance the reactivity of nanoparticles and degradation rates of aquatic contaminants acting through the synergistic effect between bimetallic system and composite [12]. According to this idea, iron-copper oxides nanocomposites have been synthesized to enhance dyes removal [3,7,13,14], but the degradation of organic dyes using Fe-Cu nanocomposites remains a scarcely explored area.…”

Removal of Indigo Carmine by a Ni Nanoscale Oxides/Schoenoplectus acutusComposite in Batch and Fixed Bed Column Systems

“…The advantages of bimetallic nanoparticles include high surface area and density of reactive surface sites; catalytic effects, which are effective in hydrodehalogenation reactions (10). Previously, it was observed that the combination of porous materials and metal nanoparticles is one of the interesting areas of interdisciplinary research in water treatments (11)(12)(13).…”