Figure 6

SEM images and corresponding EDX spectra of the three selected biosorbents (R: R. kutum scales; O: O. mykiss scales; C: C. glaucum shells): (1) the selected white (W) and dark (D) spots on the samples (× 200 magnification), (2) EDX spectra of the white (upper) and dark (lower) spots before Pb biosorption, (3) EDX spectra of the white (upper) and dark (lower) spots after Pb biosorption. Insets: Elemental composition (weight percentage).