Effects of Cu(II) on the Adsorption Behaviors of Cr(III) and Cr(VI) onto Kaolin

Figure 2

Intraparticle diffusion plots for Cr(III) (a) or Cr(VI) (b) adsorption onto kaolin in the absence and presence of Cu(II) (adsorption conditions: initial concentration for Cr(III) = 300 mg·L⁻¹, for Cr(VI) and Cu(II) = 200 mg·L⁻¹, temperature = 25°C, pH = 4.5, and equilibrium time = 120 min).

(a)

(b)