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the percentage of removal of 96.7%, and then it decreases to 95, 94, to 81.7% by
increasing the initial concentration of Cr(VI) ions of 0.4, 0.5, and 0.6 mg/l, respectively. At the lower initial metal ion concentration, there are sufficient active centers
on the surface of the adsorbent, and therefore the percentage of removal is higher.
9.3.7.3 Time of Adsorption
The experiment was performed over the period of 180 min, at 2 l solutions of Cr(VI)
with different initial concentration, using 2.5 g/l clayey diatomite, at pH 3, room temperature, and 400 rpm. The dependence of the concentration and the adsorbed amount
75
80
85
90
95
100
0.25 0.5 1.5 2.5 3.5 4.5 5.5
% Removal
m [g]
Fig. 9.7 Effect of amount of adsorbent to the rate of removal of Cr(VI) ions
Fig. 9.8 Effect of initial concentration on the adsorption process of Cr(VI) ions in clayey diatomite
9 Removal of Chromium(VI) from Aqueous Solution by Clayey Diatomite: Kinetic…
the percentage of removal of 96.7%, and then it decreases to 95, 94, to 81.7% by
increasing the initial concentration of Cr(VI) ions of 0.4, 0.5, and 0.6 mg/l, respectively. At the lower initial metal ion concentration, there are sufficient active centers
on the surface of the adsorbent, and therefore the percentage of removal is higher.
9.3.7.3 Time of Adsorption
The experiment was performed over the period of 180 min, at 2 l solutions of Cr(VI)
with different initial concentration, using 2.5 g/l clayey diatomite, at pH 3, room temperature, and 400 rpm. The dependence of the concentration and the adsorbed amount
75
80
85
90
95
100
0.25 0.5 1.5 2.5 3.5 4.5 5.5
% Removal
m [g]
Fig. 9.7 Effect of amount of adsorbent to the rate of removal of Cr(VI) ions
Fig. 9.8 Effect of initial concentration on the adsorption process of Cr(VI) ions in clayey diatomite
9 Removal of Chromium(VI) from Aqueous Solution by Clayey Diatomite: Kinetic…