Adsorptive Removal of Cadmium from Aqueous Solutions

5 ADSORPTIVE REMOVAL OF CADMIUM FROM AQUEOUS SOLUTIONS 

FIGURE 6.24 Influence of pH on the adsorption of Cd(II) by different activated carbons. (Courtesy C.P. Huang. With permission.) 

FIGURE 6.25 Isotopic exchange kinetics as a function of pH of CdClj solution. (Source Dobrowolski, R., Jaroniec, M., and Kosmulski, M., Carbon, 24, 15, 1986. With permission.) 

Bhattacharya and coworkers, Reed and Nonavinakere, and Rubin and Mercer smdied the influence of chelating agent EDTA on the adsorptive removal of Cd(n) from aqueous solutions by activated carbons. Although Rubin and Mercer found little effect of the chelating agent on the adsorption, Bhattacharya and coworkers did find an inaease in adsorption in the presence of EDTA, at least in the case of basic carbons. These coworkers even proposed the formation of an electron donor-acceptor 

Carbon Sample Surface Area (mVg) Maximum Amount of Cd(ll) Adsorbed (mg/g) pH of Slurry Ion Exchange Capacity (meq/g) 

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