Preparation of green synthesized copper oxide nanoparticles for efficient removal of lead from wastewaters

Abstract

Green synthesis is a clean and eco-friendly process in which metal nanoparticles can be produced by the reaction between a metal salt solution and plant organ extract. In the present study, three copper oxide nanoparticles were green synthesized from the leaf extracts of astragalus (Astragalus membranaceus), rosemary (Salvia rosmarinus), and mallow (Malva sylvestris) as predominant plant cover in the study area was characterized. The effectiveness of three green synthesized nanoparticles in the adsorption of lead ions from polluted water was studied. According to the results, the removal efficiencies of the copper oxide nanoparticles synthesized from astragalus (A-CuO-NPs), rosemary (R-CuO-NPs), and mallow leaf extract (M-CuO-NPs) especially at the highest initial concentration of lead (1.5 mM), were 88.4%, 84.9%, and 69.6%, respectively. Probably due to the smooth morphology and more uniform configuration of the M-CuO-NPs, the changes between equilibrium adsorption (q_e) and equilibrium concentration (C_e) were more regular than those of the A-CuO-NPs and R-CuO-NPs. Therefore, the best fit of the data to the Langmuir and Freundlich isotherms belonged to the adsorption of lead onto the M-CuO-NPs. According to the results reported herein, the copper oxide nanoparticles synthesized from different plant covers are efficient adsorption agents for lead from wastewaters solution.

Graphical Abstract

Novelty statement

1. Comparison of the efficiency of copper oxide nanoparticles prepared by green synthesis method using the leaf extracts of astragalus (Astragalus membranaceus), rosemary (Salvia rosmarinus) and mallow (Malva sylvestris) plants in removing lead ions from wastewater.

2. Astragalus, as an abundant plant cover in the study area, has a capable leaf extract for green synthesis of copper nanoparticles, which its efficiency for the removal of toxic metal ions from aqueous solutions has not been already studied in previous researches.

Keywords:

• Adsorption
• copper oxide
• green synthesis
• lead
• nanoparticles
• removal efficiency

Acknowledgments

The authors are grateful to the Department of Soil Science, School of Agriculture, Shiraz University, Shiraz, Iran.

Author contributions

The manuscript was based on a draft written through the contributions of AZ and RGH. Both authors read and approved the final manuscript.

Disclosure statement

The authors declare that they have no competing interests.

Data availability statement

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Additional information

Funding

This work was supported by Shiraz University.