Removal of arsenic with functionalized multi-walled carbon nanotubes (MWCNTs-COOH) using the magnetic method (Fe3O4) from aqueous solutions

Masoumeh Khorasani Alamdari; Ata Allah Nadiri; Hossein Ghaforian; Sina Sadeghfam

doi:10.1039/d3ra04803a

Removal of arsenic with functionalized multi-walled carbon nanotubes (MWCNTs-COOH) using the magnetic method (Fe₃O₄) from aqueous solutions

RSC Adv. 2023 Aug 23;13(36):25284-25295. doi: 10.1039/d3ra04803a. eCollection 2023 Aug 21.

Authors

Masoumeh Khorasani Alamdari¹, Ata Allah Nadiri², Hossein Ghaforian³, Sina Sadeghfam⁴

Affiliations

¹ Department of Marine Science and Technology, Islamic Azad University North Tehran Branch Tehran Iran khorasanimasoume@yahoo.com.
² Department of Natural Sciences, Tabriz University Tabriz Iran Nadiri.ata@gmail.com.
³ Marine Science and Technology Department, Islamic Azad University North Tehran Branch Tehran Iran Ghaforian25@yahoo.com.
⁴ Department of civil Engineering, Faculty of Engineering, University of Maragheh Iran s.sadeghfam@gmail.com.

Abstract

Heavy metals such as arsenic are one of the most important water pollutants and cause many environmental problems. One of the mechanisms for removing arsenic from aqueous media is the adsorption process. In this study, we investigated the efficiency of magnetized multi-walled carbon nanotubes with iron oxide (Fe₃O₄) nanoparticles. The precipitation method was used to synthesize Fe₃O₄ on PAC-(Fe₃O₄-f/MWCNTs) functionalized multi-walled carbon nanotubes. The effects of pH, contact time, amount of adsorbent, and contaminant concentration on the adsorption process were examined. Residual arsenic concentration was measured using induction chromatography and inductively coupled plasma mass spectrometry (ICP-MS). The physical and structural characteristics of the adsorbent were analyzed using XRD, TEM, FT-IR, TGA-DTA, BET, FESEM-EDS, Raman spectrum and X-ray. Optimal conditions for arsenic removal were pH = 2, As concentration = 6 mg L^-1, and contact time = 30 minutes, using 0.02 g of adsorbent at room temperature. Also, fitting regression curves to the results showed that the Freundlich model (R² > 0.9981) and a pseudo-second-order model (R² = 1) best describe the isothermal and kinetic models of the adsorption process, respectively.