Removal of Pb(II) from Aqueous Solutions with Manganese Oxide-Modified Diatomite

Figure 4

(a) XRD patterns of natural diatomite and the Mn/diatomite samples prepared at different hydrothermal temperatures (experimental conditions: hydrothermal time of 16 h and molar ratio of KMnO₄/HCl 1 : 8); (b) XRD pattern of the Mn/diatomite sample (experimental conditions: hydrothermal time and temperature of 24 h and 80°C, respectively, and molar ratio of KMnO₄/HCl 1 : 4); (c) nitrogen adsorption-desorption isotherms; (d) pore-size distributions of diatomite and Mn/diatomite (experimental conditions: hydrothermal time and temperature of 24 h and 80°C, respectively, and molar ratio of KMnO₄/HCl 1 : 4).

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(b)

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