Graphene oxide/polypyrrole composites for highly selective enrichment of U(vi) from aqueous solutions

Abstract

Graphene oxide/polypyrrole (GO/PPy) composites were synthesized via a dielectric barrier discharge (DBD) plasma technique in nitrogen conditions, and characterized by scanning electron microscopy (SEM), Raman spectroscopy, thermal gravimetric analysis (TGA), Fourier transformed infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The sorption of U(VI) ions on GO/PPy composites from aqueous solutions was investigated as a function of contact time, pH, ionic strength and U(VI) initial concentrations. The sorption capacity of U(VI) on GO/PPy composites was much higher than those of U(VI) on GO, PPy and many other materials of today. The sorption of U(VI) on GO/PPy composites obeyed the Langmuir model, and was mainly attributed to surface complexation via the coordination of U(VI) ions with oxygen-and nitrogen-containing functional groups. The selectivity sorption of U(VI) ions on GO/PPy composites in the presence of other metal ions (i.e., Co(II), Ni(II), Cd(II), Sr(II), Zn(II)) indicated an overall preference for U(VI) ions. Moreover, the GO/PPy composites could be regenerated through the desorption of adsorbed U(VI) ions by using 1.0 M HCl solution, and cycling reused without an obvious decrease of sorption capacity. All these performances indicate that GO/PPy composites are suitable materials for the highly selective removal and preconcentration of U(VI) ions from aqueous solutions in environmental pollution management.

High performance resistive switching memory organic films prepared through PPy growing on graphene oxide substrate

“…The result suggests that the groups of C-O bond have taken part in the interaction with PPy. In the C 1 s spectrum of the GO-PPy film, moreover, the deconvoluted peak at 285.7 eV is assigned to C-N bond in PPy [38].…”

“…Figure 6b shows the XPS C 1 s spectra measured from the GO-PPy composite film and pristine GO, respectively. As for the pristine GO, the peak at BE of 284.5 eV is attributed to the C-C bond and C=C bond, the peak at 286.7 eV is assigned to the C-O bonds (C-OH and C-O-C), and the weak peak at 288.5 eV is assigned to the C=O bonds (C=O and O=C-OH) [38]. It is found that the peak of C-O bond in the GO-PPy film is dramatically reduced as compared with the pristine GO.…”

Sorption and desorption properties of Eu(III) on attapulgite

“…increases with pH increasing and is also affected by ionic strength. From the precipitation constant of Eu(OH) 3 (s) (K sp = 3.4 9 10 -22 ) [20], the precipitation curve of Eu(OH) 3 at Eu(III) initial concentration of 1.4 9 10 -6 mol/L was calculated and was also shown in Fig. 4.…”

“…The radionuclides in the environment can be accumulated through the food chain and at last are deposited in human body, which is dangerous to human health. Thereby, it is crucial to eliminate the radionuclides from the radioactive wastewater as much as possible [1][2][3][4]. Among the long-lived trivalent lanthanides and actinides, Eu(III) is usually considered as a homologue for the trivalent lanthanides and actinides because the physicochemical properties of Eu(III) are very similar with those of other trivalent lanthanides and actinides [5,6].…”

Illite-supported nanoscale zero-valent iron for removal of 238U from aqueous solution: characterization, reactivity and mechanism

“…The advantages of nZVI facilitate remediation of hazardous wastes contamination that the small particle size and large surface area per unit mass of nanoparticles [12,[14][15][16]. Nanoscale zero-valent iron has the potential for efficient and cost effective remediation of contaminated solutions [13,[17][18][19]. However, the frequent aggregation of nZVI reduces its efficiency [20,21].…”