Figure 1
TEM images of (a) Fe3O4 and (b) Fe3O4@PEG@IL.
Figure 2
FTIR spectra of Fe3O4 and Fe3O4@PEG@IL.
Figure 3
TGA of Fe3O4@PEG@IL.
Figure 4
Effect of solution pH on the adsorption rate of Cr(vi).
Figure 5
Effect of solution temperature on the adsorption rate of Cr(vi).
Figure 6
Effect of adsorbent dosage on the adsorption rate of Cr(vi).
Figure 7
Effect of adsorption time on the adsorption rate of Cr(vi).
Figure 8
Influence of the alkyl chain length of the imidazole cation on the adsorption rate of Cr(vi).
Figure 9
Adsorption rate of Cr(vi) in the presence of coexisting heavy metal cations.
Figure 10
Adsorption/desorption experiments of Fe3O4@PEG@IL for Cr(vi). Temperature: 25°C; adsorption time: 2.5 h; desorption reagent: 8% hydrazine hydrate.