Indonesian kaolin supported nZVI (IK-nZVI) used for the an efficient removal of Pb(II) from aqueous solutions: kinetics, thermodynamics and mechanism

Abstract

A remarkably efficient Indonesian Kaolin (IK) supported nano zerovalent iron composite (IK-nZVI) has been synthesized, and subjected to the elimination Pb(II) from the wastewater. The results were authenticate the nZVI nanoparticles have a chain shape and establish as separable nanospheres with an average size (29.95 nm) on the surface of IK. The FTIR spectra demonstrate the presence of Al-O as well as Si-O bonds. XRD results demonstrate the presence of zerovalent iron. SEM confirmed less agglomeration of Fe(0) nanoparticles which improves the mechanical strength. The weak signals of Fe and O confirm the establishment of zerovalent iron in nanocomposite. TEM demonstrates that the nanocomposite has a chain like structure. Pb(II)percentage removal was improved by rise in the IK-nZVI amount which results in rising the adsorption site. The nanocomposite had on optimum Pb(II) sorption at pH range of 4.5–6.5. The amount adsorbent increasing with the Pb(II) removal percentage was decreased. Kinetics study demonstrated that Pb(II) sorption was accomplished through more than one processes. IK was proved active support to progress the dispersion, and steadiness of IK-nZVI nanocomposite. The sorption processes pollutant was estimated through the kinetics models, and different sorption isotherm equations like Langmuir (LM), Langmuir-Freundlich (L-F), and Freundlich (FL) isotherms. The IK-nZVI typically accompanies outstanding Pb(II) removal efficiency of 98% and 96.05% with a span of 5 and 10 min for low and high concentrations, respectively. Significantly, the results reveal the maximum adsorption capability of the IK-nZVI is 192.0 mg/g. The thermodynamic study shown endothermic and spontaneous adsorption onto the IK-nZVI surface. Specifically, the IK-nZVI nanocomposite possesses key advantages in terms of simple method, nature friendly, cost-effectiveness, and decent adsorption efficiency for the potential elimination of toxic metal ion (Pb(II)) in the aqueous phase.