Composite of bentonite/CoFe₂O₄/hydroxyapatite for adsorption of Pb (II)

Abstract

In this contribution, a composite from bentonite (B), CoFe2O4 (CF), and hydroxyapatite (HAP) was developed by chemical synthesis route for adsorption of a lead ion, Pb (II) from wastewater. Initially, a composite of B/CF was synthesized by varying the weight ratio of CF, i.e., (1–x)B/(x)CF (x = 0.05, 0.15, 0.25, 0.50), followed by ternary composite synthesis, which was formulated from the sample of (0.85B/0.15CF) and different weight ratios of HAP, i.e., (1–y)[(0.85B/0.15CF)]/yHAP where y = 0.25, 0.35 and 0.45 weight ratios of HAP. The sample of 0.85B/0.15CF was found to be optimal in its adsorption capacity of about 20 mg g−1 from the binary composite samples, while among the ternary composites, a sample with a composition of 0.65[(0.85B/0.15CF)]/0.35HAP revealed an optimum adsorption capacity of about 36 mg g−1, which was then selected for further studies. The adsorption kinetics of Pb (II) by the optimum 0.65[(0.85B/0.15CF)]/0.35HAP sample was studied at different contact times from 30–120 min, where the equilibrium was reached at around 90 min of contact time and the kinetic behavior adopted Pseudo-second order adsorption mechanism. The initial concentration of Pb (II) was also varied from 50–200 mg l−1 to study the adsorption isotherm, which resulted that adsorption capacity of 0.65[(0.85B/0.15CF)]/0.35HAP towards Pb (II) was increased to about 66 mg g−1 and the adsorption isotherm data best fitted with Langmuir adsorption isotherm model. Therefore, the result of this study pinpoints that the present composite material is a potential candidate for the adsorption of Pb (II) ion.

Optimization of adsorption of methyl orange from aqueous solution by magnetic CoFe2O4/ZnAl-layered double hydroxide composite using response surface methodology

“…Figure 2 crystallographic density of 5.27 g•cm −3 , which is in an agreement to the theoretical density of about 5.29 g•cm −3 [39]. Details of the crystallographic planes and the corresponding (hkl) of the planes are reported elsewhere [10].…”

“…In this study, Freundlich and Langmuir adsorption isotherms were used to study the adsorption mechanism [10].…”

“…Therefore, it is crucial to remove dyes from contaminated water bodies before discharging into the environment using various technologies such as photocatalytic degradation, reverse osmosis, nanofiltration, flocculation, and adsorption [8]. Among the aforementioned methods, the adsorption approach has been widely applicable due to its efficiency, economic feasibility, recycling of adsorbent, and environmental friendliness [9,10]. In recent times, adsorbents like LDH materials have gained substantial research attention by researchers.…”

Synthesis and characterizations of (Mg, Co, Ni, Cu, Zn)O high-entropy oxides

“…Metal oxides play a very important role in today's technological advancements such as energy harvesting and production, photo-catalysis, high-temperature contact materials, and environmental pollution preventions supported by nanotechnology [14][15][16][17][18]. High entropy oxides (HEOs) are established from these metal oxides and are entropy-stabilized solid-solutions where nearly equimolar multi-components of the oxides are brought into a singlephase material [19][20][21][22] through thermodynamic stabilizations [23].…”

Comparative Study on Removal Efficiency of Methylene Blue from Wastewater by using Nano-Scaled Sugarcane Bagasse Ash and Jema Silica Sand

“…Where q e (mg/g) is the equilibrium adsorption capacity, C o is the initial concentration of methylene blue, C e (mg/L) is the concentration of methylene blue at equilibrium time, C t is the concentration of methylene blue at a given time, V is the volume of solution, m is mass of the adsorbent, η (removal efficiency) according to [49][50][51][52].…”