A green method for removing chromium (VI) from aqueous systems using novel silicon nanoparticles: Adsorption and interaction mechanisms

Sajid Mehmood; Mohsin Mahmood; Avelino Núñez-Delgado; Juha M Alatalo; Ahmed S Elrys; Muhammad Rizwan; Jiechang Weng; Weidong Li; Waqas Ahmed

doi:10.1016/j.envres.2022.113614

A green method for removing chromium (VI) from aqueous systems using novel silicon nanoparticles: Adsorption and interaction mechanisms

Environ Res. 2022 Oct:213:113614. doi: 10.1016/j.envres.2022.113614. Epub 2022 Jun 13.

Authors

Sajid Mehmood¹, Mohsin Mahmood¹, Avelino Núñez-Delgado², Juha M Alatalo³, Ahmed S Elrys⁴, Muhammad Rizwan⁵, Jiechang Weng⁶, Weidong Li⁷, Waqas Ahmed⁸

Affiliations

¹ Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, Hainan University, Haikou, 570100, China; College of Ecology and Environment, Hainan University, Haikou City, 570100, China.
² Department of Soil Science and Agricultural Chemistry, Engineering Polytechnic School, University of Santiago de Compostela, Campus Univ. s/n, 27002, Lugo, Univ. Santiago de Compostela, Spain.
³ Environmental Science Center, Qatar University, Doha, Qatar.
⁴ Soil Science Department, Faculty of Agriculture, Zagazig University, Zagazig, 44511, Egypt.
⁵ Agricultural Research Station, Office of VP for Research & Graduate Studies, Qatar University, 2713, Doha, Qatar.
⁶ Hainan Provincial Ecological and Environmental Monitoring Center, 571126, China.
⁷ Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, Hainan University, Haikou, 570100, China; College of Ecology and Environment, Hainan University, Haikou City, 570100, China. Electronic address: weidongli@hainanu.edu.cn.
⁸ Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, Hainan University, Haikou, 570100, China; College of Ecology and Environment, Hainan University, Haikou City, 570100, China. Electronic address: drwaqas@hainanu.edu.cn.

PMID: 35710023
DOI: 10.1016/j.envres.2022.113614

Abstract

In the present study, we used the horsetail plant (Equisetum arvense) as a green source to synthesize silicon nanoparticles (GS-SiNPs), considering that it could be an effective adsorbent for removing chromium (Cr (VI)) from aqueous solutions. The characterization of GS-SiNPs was performed via Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and X-ray photo electron spectroscopy (XPS) techniques. The batch test results of Cr (VI) adsorption on GS-SiNPs showed a high adsorption capacity, reaching 87.9% of the amount added. The pseudo-second order kinetic model was able to comprehensively explain the adsorption kinetics and provided a maximum Cr (VI) adsorption capacity (Q_e) of 3.28 mg g^-1 (R² = 90.68), indicating fast initial adsorption by the diffusion process. The Langmuir isotherm model fitted the experimental data, and accurately simulated the adsorption of Cr (VI) on GS-SiNPs (R² = 97.79). FTIR and XPS spectroscopy gave further confirmation that the main mechanism was ion exchange with Cr and surface complexation through -OH and -COOH. Overall, the results of the research can be of relevance as regards a green and new alternative for the removal of Cr (VI) pollution from affected environments.

Keywords: Adsorption; Chromium; Green synthesis; Horsetail (Equisetum arvense); Silicon nanoparticles.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adsorption
Chromium / analysis
Hydrogen-Ion Concentration
Kinetics
Nanoparticles*
Silicon
Spectroscopy, Fourier Transform Infrared
Water / chemistry
Water Pollutants, Chemical* / analysis

Substances

Water Pollutants, Chemical
Water
Chromium
chromium hexavalent ion
Silicon