Studies of Adsorption of Heavy Metals onto Spent Coffee Ground: Equilibrium, Regeneration, and Dynamic Performance in a Fixed-Bed Column

Figure 7

Effect of the bed height on the breakthrough curves of (a) Cd²⁺, (b) Cu²⁺, and (c) Pb²⁺. Experimental conditions: 0.1 mM initial metal concentration, pH 4.5, and 25°C.

(a)

(b)

(c)