Heavy metals removal by EDTA-functionalized chitosan graphene oxide nanocomposites

Asif Shahzad,Waheed Miran,Seong-Rin Lim,Jiseon Jang,Mohsin Nawaz,Kashif Rasool,Dae Sung Lee

doi:10.1039/c6ra28406j

Abstract

Graphene-based two-dimensional materials have been explored in a variety of applications, including the treatment of heavy-metal-rich water/wastewater.

Highlights

IntroductionMany techniques have been developed for the removal of heavy metals from wastewater, such as chemical precipitation, ion exchange, reverse osmosis, membrane ltration, electrolysis, and adsorption
The discharge of wastewater containing heavy metals into the environment has increased continuously as a result of various industrial activities, such as metal nishing, electroplating, metal smelting, chemical engineering, papermaking, mining, and agriculture.[1,2] Heavy metal contamination in such effluents presents a serious threat to the environment and human health because of their toxicity, non-biodegradability, carcinogenicity, and bioaccumulation in living organisms.[3,4] For instance, Pb poses several risks to human health, causing insomnia, pain, dizziness, anemia, irritability, muscle weakness, hallucinations, and renal damage.[5]
The Fourier transform infrared (FT-IR) results con rmed that ethylenediaminetetraacetic acid (EDTA)-magnetic chitosan (MCS)/graphene oxide (GO) contained numerous oxygen and nitrogen functional groups (Fig. 1a)

Summary

Introduction

Many techniques have been developed for the removal of heavy metals from wastewater, such as chemical precipitation, ion exchange, reverse osmosis, membrane ltration, electrolysis, and adsorption. The presence of a wide range of consecutive oxygen functional groups on the GO surface and large surface area are characteristics that make GO an excellent adsorbent for the removal of heavy metals and several other pollutants.[11] the large speci c surface area of GO provides abundant attachment sites for the functionalization of other compounds, such as chitosan (CS) and ethylenediaminetetraacetic acid (EDTA). This can increase the number of surface functional groups, which might enhance heavy metal adsorption. The adsorption behavior of synthesized EDTA-MCS/GO nanocomposites was investigated for divalent Pb2+, Cu2+, and trivalent As3+ ions in aqueous solution

Experimental work

Adsorption experiments

Results and discussion

Metal ion adsorption

Conclusion