The Improvement of Natural Thai Bentonite Modified with Cationic Surfactants on Hexavalent Chromium Adsorption from an Aqueous Solution

Figure 4

Preedge feature of normalized Cr K-edge XANES spectra of references and samples included the (a) Cr(III) reference, (b) Cr(VI) reference, (c) NTB+Cr(III), (d) 1HDTMA+Cr(III), (e) 1CPC+Cr(III), (f) 1HDTMA+Cr(VI), and (g) 1CPC+Cr(VI).

(a)

(b)