Adsorption of Nitrate onto ZnCl₂-Modified Coconut Granular Activated Carbon: Kinetics, Characteristics, and Adsorption Dynamics

Table 3

Langmuir, Freundlich, and Temkin model constants for nitrate adsorption.

Adsorbent	Langmuir			Freundlich			Temkin
	(mgN·g^−1)	(L·mg^−1)	R^2	(mgN·g^−1)·(L·mg^−1)^1/n		R^2	(L·mg^−1)	(J·mol^−1)	R^2
ZnCl2-modified CGAC	14.01	0.0058	0.970	0.13	0.813	0.982	0.35	1.0055	0.828
CGAC	0.28	0.0294	0.817	0.00851	0.746	0.962	0.24	0.0707	0.745

is the equilibrium concentration (mg·L⁻¹); is the monolayer saturation adsorption capacity; is the Langmuir constant (L·mg⁻¹); is the adsorbent-adsorbate relative affinity in the adsorption process ((mgN·g⁻¹)·(L·mg⁻¹)^1/n); is equilibrium blinding constant (L·mg⁻¹); and is the Temkin constant related to the heat of adsorption.