Selective solid-phase extraction and analysis of trace-level Cr(III), Fe(III), Pb(II), and Mn(II) Ions in wastewater using diethylenetriamine-functionalized carbon nanotubes dispersed in graphene oxide colloids

• Published in: Talanta (Oxford) 2016-01, Vol.146, p.358-363
• Main Authors: Zhu, Xiangbing, Cui, Yuemei, Chang, Xijun, Wang, Hua
• Format: Article
• Language: English
• Subjects: Diethylenetriamine; Graphene oxide; Heavy metal ions; Inductively coupled plasma optical emission spectrometry; Multi-walled carbon nanotubes; Solid-phase extraction
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2015.08.073

Multi-walled carbon nanotubes (MCNTs) were dispersed in graphene oxide (GO) colloids to be further functionalized with diethylenetriamine (DETA), resulting in GO–MCNTs–DETA nanocomposites for the solid-phase extraction and analysis of Cr(III), Fe(III), Pb(II), and Mn(II) ions at the trace levels in wastewater. Inductively coupled plasma optical emission spectrometry (ICP–OES) indicates that this new solid-phase sorbent could facilitate the maximum static adsorption capacities of 5.4, 13.8, 6.6 and 9.5mgg−1 for Cr(III), Fe(III), Pb(II), and Mn(II) ions, respectively, showing the adsorption capacity up to 95% within about 30min. Moreover, the detection limits of the GO–MCNTs–DETA-based analysis method were found to be 0.16, 0.50, 0.24 and 0.38ngmL−1 for Cr(III), Fe(III), Pb(II), and Mn(II) ions, respectively, with the relative standard deviation of lower than 3.0% (n=5). Importantly, common coexisting ions showed no significant interference on the separation and pre-concentration of these heavy metal ions at pH 4.0. Subsequently, the GO–MCNTs–DETA sorbent was successfully employed for the separation and analysis of trace-level Cr(III), Fe(III), Pb(II), and Mn(II) ions in wastewater samples yielding 75-folds concentration factors. Multi-walled carbon nanotubes (MCNTs) were dispersed in graphene oxide (GO) colloids and functionalized with diethylenetriamine (DETA) for the selective extraction and analysis of trace-level Cr(III), Fe(III), Pb(II), and Mn(II) ions in wastewater. [Display omitted] •Carbon nanotubes were dispersed in graphene oxide with improved aqueous dispersion.•Diethylenetriamine was used for the selective solid-phase sorbent for metal ions.•Selective extractions were obtained for Cr(III), Fe(III), Pb(II), and Mn(II) ions.•Cr(III), Fe(III), Pb(II), and Mn(II) ions in wastewater were sensitively analyzed.