Eco‐Friendly Technique for Preparation of ZnO Nanoparticles: Pd(II) Ions Adsorption

Abstract

A novel eco-friendly procedure was developed to adsorb Pd 2+ ions from wastewaters using the green synthesized zinc oxide (ZnO) nanoparticles (NPs). ZnO NPs were easily produced using zinc nitrate through Centaurea cyanus extract as a reducing agent at ambient conditions. X-ray diffraction results demonstrated that ZnO NPs have a highly crystalline hexagonal structure. Fourier transform infrared spectral analysis indicated an active contribution of C. cyanus-derived biomolecules in zinc ions bioreduction. ZnO NPs were properly dispersed and had a hexagonal shape. The impact of process parameters like initial pH of solution, adsorption dosage, Pd 2+ ions initial concentration, and contact time on the Pd 2+ ions adsorption from the effluent of a petrochemical company was evaluated. The Freundlich isothermal model could excellently legitimize a multilayer adsorption. The adsorption process followed a pseudo-second-order reaction kinetic, i.e., chemisorption process.

Adsorption mechanism and modeling of radionuclides and heavy metals onto ZnO nanoparticles: a review

“…However, it is not recommended to conclude on the chemical or physical nature of adsorption based on the good fit of the Langmuir or Freundlich model alone, rather a reliable conclusion would involve a holistic consideration of the isotherm, kinetics thermodynamics, desorption, and mechanistic interpretations. Furthermore, the favorability of the adsorption process or efficient interaction between the metal ions in solution and ZnONPs can be deduced from the Freundlich n value in the range of 1-10 (Chukwuemeka-Okorie et al 3, it is observed that the values of n obtained for heavy metals and radionuclides adsorption were all in the favorable range except for a few studies involving the adsorption of Cu(II), Pb(II) and Pd(II) (Somu and Paul 2018;Primo et al 2020;Leiva et al 2021;Davarnejad and Nikandam 2022). This shows that metal contaminants in water and ZnONPs have a good affinity for efficient water decontamination.…”

“…Zinc oxide nanoparticles (ZnONPs) in particular have attracted a lot of attention among nanoparticle adsorbents because of their biocompatibility, affordable price, long-term stability, surface characteristics, photocatalytic activity, nontoxicity, and powerful antibacterial activity against microbes often found in water (Akbar et al 2019;Gu et al 2020;Akpomie et al 2021). As a result, various studies on the adsorption of heavy metals and radionuclides onto ZnONPs have been conducted (Kumar et al 2013;Kaynar et al 2014;Azizi et al 2017;Lagashetty et al 2020;Gu et al 2020;Alqahtany and Khalil 2021;Davarnejad and Nikandam 2022). Due to the importance of ZnONPs in water treatment, a review of their capability as a water decontaminating agent via adsorption and photocatalysis was written (Bharti et al 2022).…”

Basella alba Leaves‐Assisted Eco‐Fabrication of Ag/ZnO Nanocomposites for Anti‐Bactericidal Activity and Catalytic Degradation of Anthropogenic Pollutants

“…This may be due to the presence of a huge reduction potential that hampers the transfer of electron molecules between the donor molecule (NaBH 4 ) and the acceptor (dye molecule). When a small quantity of nano-catalyst was put into the catalytic reaction, the rate of the reaction was accelerated and the degradation reaction was made kinetically favorable [27]. The viability of degradation with the pure plant extract, without the nano-catalyst, was also evaluated in the dye degradation process (Supporting Information Fig.…”