Effect of Initial Aerobic Granules Concentration on Biosorption Kinetics

Effect of Initial Aerobic Granules Concentration on Specific Biosorption Capacity

The effect of initial aerobic granules concentration on Cd2+, Cu2+, and Zn2+ biosorption capacities was shown in the Figs 11.13-11.15, respectively (Xu, 2006). It appears that an increased granules

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Initial Cd2+ concentration (mg/l)

Fig. 11.10. Effect of initial Cd2+ concentration on k (Liu et al., 2003a).

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Initial Cd2+ concentration (mg/l)

Fig. 11.10. Effect of initial Cd2+ concentration on k (Liu et al., 2003a).

Initial Cu2+ concentration (mg/l)

Fig. 11.11. Effect of initial Cu2+ concentration on k (Xu, 2006).

Initial Cu2+ concentration (mg/l)

Fig. 11.11. Effect of initial Cu2+ concentration on k (Xu, 2006).

Initial Zn2+ concentration (mg/l)

Fig. 11.12. Effect of initial Zn2+ concentration on k (Liu et al., 2002).

Fig. 11.13. Effect of initial aerobic granules concentration on cadmium biosorption capacity (Xu, 2006).

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Initial aerobic granules concentration (mg/l)

Fig. 11.14. Effect of initial aerobic granules concentration on copper biosorption capacity (Xu, 2006).

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Initial aerobic granules concentration (mg/l)

Fig. 11.14. Effect of initial aerobic granules concentration on copper biosorption capacity (Xu, 2006).

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Initial aerobic granules concentration (mg/l)

Fig. 11.15. Effect of initial aerobic granules concentration on zinc biosorption capacity (Xu, 2006).

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Initial aerobic granules concentration (mg/l)

Fig. 11.15. Effect of initial aerobic granules concentration on zinc biosorption capacity (Xu, 2006).

concentration results in a decreased specific biosorption capacity for all three kinds of metal ions.

Effect of Initial Aerobic Granules Concentration on Overall Biosorption Rate Constant

Initial biosorbent and metal concentrations would have a profound effect on the biosorption kinetics (Liu et al., 2002, 2004b). Figure 11.16 shows the relationship between the overall biosorption rate constant (k) of Cd2+ and initial aerobic granules concentration (Liu et al., 2003a). The overall biosorption rate constant of Cd2+ decreased with the increase of the initial aerobic granules concentration, i.e. k decreased from 0.01 min-1 at the initial aerobic granules concentration of 50 mg/l to 0.083 min-1 at the initial granules concentration of 200 mg/l.

Figure 11.17 displays the effect of initial granule concentration on k of copper (Xu, 2006). There was a decline of the overall uptake rate constant of copper from 0.12 min-1 to 0.045 min 1 when the initial granules concentration was increased from 50 mg/l to 100 mg/l. Beyond the initial aerobic granules concentration of 100 mg/l, k of copper seems to be less dependent on the initial aerobic granule concentration. A similar trend was observed in the biosorption of Zn2+ by aerobic granules (Fig. 11.18).

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Initial aerobic granules concentration (mg/l)

Fig. 11.16. Effect of initial aerobic granules concentration on the cadmium biosorption rate constant (Liu et al., 2003a).

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Initial aerobic granules concentration (mg/l)

Fig. 11.16. Effect of initial aerobic granules concentration on the cadmium biosorption rate constant (Liu et al., 2003a).

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Initial aerobic granules concentration (mg/l)

Fig. 11.17. Effect of initial aerobic granules concentration on the copper biosorption rate constant (Xu, 2006).

0.25

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Initial aerobic granules concentration (mg/l)

Fig. 11.18. Effect of initial aerobic granules concentration on the zinc biosorption rate constant (Liu et al., 2002).

Fig. 11.17. Effect of initial aerobic granules concentration on the copper biosorption rate constant (Xu, 2006).

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Initial aerobic granules concentration (mg/l)

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