Zero Valent Iron Nanoparticle-Loaded Nanobentonite Intercalated Carboxymethyl Chitosan for Efficient Removal of Both Anionic and Cationic Dyes

Abdelazeem S Eltaweil; Ashraf M El-Tawil; Eman M Abd El-Monaem; Gehan M El-Subruiti

doi:10.1021/acsomega.0c06251

Zero Valent Iron Nanoparticle-Loaded Nanobentonite Intercalated Carboxymethyl Chitosan for Efficient Removal of Both Anionic and Cationic Dyes

ACS Omega. 2021 Mar 1;6(9):6348-6360. doi: 10.1021/acsomega.0c06251. eCollection 2021 Mar 9.

Authors

Abdelazeem S Eltaweil¹, Ashraf M El-Tawil¹, Eman M Abd El-Monaem¹, Gehan M El-Subruiti¹

Affiliation

¹ Department of Chemistry, Faculty of Science, Chemistry, Alexandria University, P.O. Box 426, Alexandria 21321, Egypt.

Abstract

A zero valent iron-loaded nano-bentonite intercalated carboxymethyl chitosan (nZVI@nBent-CMC) composite was fabricated and characterized by FT-IR, TEM, TEM-EDX, XRD, BET surface area, and zeta potential measurements. The as-fabricated nZVI@nBent-CMC composite exhibited excellent removal efficiency for both anionic Congo red (CR) dye and cationic crystal violet (CV) dye. The maximum uptake capacities of CR and CV onto the nZVI@nBent-CMC composite were found to be 884.95 and 505.05 mg/g, respectively. The adsorption process of both dyes well fitted with the Langmuir isotherm model and pseudo-second order kinetic model. Thermodynamic data clarified that the adsorptions of both CR and CV onto the nZVI@nBent-CMC composite are spontaneous processes. Moreover, the adsorption of CR onto the nZVI@nBent-CMC composite was found to be an exothermic process while that of CV is an endothermic process. The nZVI@nBent-CMC composite also exhibited excellent reusability for both studied dyes without noticeable loss in the removal efficiency, suggesting its validity to remove both anionic and cationic dyes from wastewater.