Adsorptive removal of Rhodamine B dye from aqueous solution by using graphene–based nickel nanocomposite

Abstract

In this work, reduced graphene oxide-nickel (RGO–Ni) nanocomposite is synthesized. X-ray diffraction (XRD), scanning electron microscopy (SEM) and SEM–EDS (Energy Dispersive X-Ray Spectroscopy) are used to study the crystalline nature, morphology and elemental composition of the RGO–Ni nanocomposite, respectively. As synthesized RGO–Ni nanocomposite is used to develop selective adsorptive removal of Rhodamine B (RhB) dye from the aqueous solution. The experiments have been performed to investigate RhB uptake via RGO–Ni nanocomposites which include, contact time (60 min), initial dye concentration (50 mg/100 ml), adsorbent dosage (0.5 mg) and pH 8 of dye solution. The equilibrium concentration is determined by using different models namely, Freundlich, Langmuir and Tempkin. Langmuir isotherm has been fitted well. Langmuir and Tempkin equations are determined to have good agreement with the correlation coefficient data. The kinetic study concluded that RhB dye adsorption follows with the pseudo-second-order kinetic model. Further, adsorption mechanism of RGO–Ni is proposed which involves three steps. The synthesized adsorbent is compared with the other adsorbents in the literature and indicates that RGO–Ni nanocomposite used in this study shown better results for a particular adsorption capacity than polymeric, natural and synthetic bioadsorbents. The regeneration and reusability experiments suggest RGO–Ni nanocomposite can be used for many numbers of times for purification/adsorption.

Adsorption kinetics, isotherm and thermodynamics studies for the removal of cationic dyes from environmental wastewater by reduced graphene oxide adsorbent synthesized via greener way

“…It is shown that about 96.84% methylene blue adsorbed within 60 min and 98% crystal violet adsorbed within 100 min and also that rate of adsorption decreases with increasing time for both dyes. Higher rate of adsorption at initial stage is due to maximum number of vacant pores on the adsorbent and high gradient of dye concentration [60]. The difference in the rate of adsorption may be due to fact that initially due to remaining vacant sites of the adsorbent, the adsorbates are getting attached very quickly.…”

Recent Advances in the Synthesis, Characterization, and Application of Carbon Nanomaterials for the Removal of Endocrine-Disrupting Chemicals: A Review

“…Carbon-based nanocomposites have a better regeneration ability. In studies on the adsorption removal of rhodamine B dye using GO-based nano-nickel composite materials, the adsorption efficiency decreased from 90% to 85% after the first recovery and decreased to 60% after the fifth recovery [ 125 ].…”

Adsorption kinetics and isotherms of binary metal ion aqueous solution using untreated venus shell

“…Adsorption has been widely used over the years because of its rather high efficiency, easy operation, relatively inexpensive, and reversibility and desorption capability [ 13 , 14 ]. Aside from the elimination of heavy metals, adsorption is regularly used for dye removal [ 14 , 15 ]. However, the cost of the adsorption process is mainly related to the adsorbent.…”