Facile Synthesis of Hollow MgO Spheres and Their Fluoride Adsorption Properties

Table 1

Kinetic parameters for fluoride adsorption on the hollow MgO spheres.

Equations	Pseudo-first-order kinetic model				Pseudo-second-order kinetic model
	C0 (mg/L)	qe, exp (mg/g)	k1 (1/min)	qe, cal (mg/g)	R^2	k2 (g/(mg min))	qe, cal (mg/g)	R^2
10	9.43	0.028	4.65	0.775	0.015	9.54	0.998

Note: k₁ is the adsorption rate constant for the pseudo-first-order reaction (1/min). k₂ is the rate constant for the pseudo-second-order reaction (g/(mg min)). q_e and q_t are the amounts of solute sorbed at equilibrium and at any time t (mg/g), respectively. qe, exp is the adsorption capacity evaluated from batch experiment, while qe, cal is the adsorption capacity calculated on the basis of the pseudo-first-order and pseudo-second-order equations.