Adsorption of Heavy Metals on Bentonitic Soil for Use in Landfill Liners

Table 6

Statistical analysis of sorption isotherms.

Metal	Model	Coefficients	Estimated value	p-level
Pb	Linear	Kd(L/g)	0.68	0.019	0.815
	Freundlich	Kf (L/g)	2.83	0.019	0.877
		n	2.79	0.005
	Langmuir	KL (L/mg)	1.73	0.034	0.946
		b (mg/g)	6.70	0.001
Cu	Linear	Kd(L/g)	0.028	0.005	0.815
	Freundlich	Kf (L/g)	0.48	0.284	0.986
		n	2.83	0.150
	Langmuir	KL (L/mg)	0.13	0.523	0.931
		b (mg/g)	2.40	0.071
Cd	Linear	Kd(L/g)	0.02	0.010	0.765
	Freundlich	Kf (L/g)	0.46	0.005	0.969
		n	2.79	0.002
	Langmuir	KL (L/mg)	0.05	0.188	0.987
		b (mg/g)	3.05	0.006
Ni	Linear	Kd(L/g)	0.04	0.020	0.964
	Freundlich	Kf (L/g)	0.25	0.014	0.987
		n	2.38	0.028
	Langmuir	KL (L/mg)	0.36	0.061	0.951
		b (mg/g)	0.87	0.003
Zn	Linear	Kd(L/g)	0.03	0.005	0.957
	Freundlich	Kf (L/g)	0.22	0.000	0.999
		n	2.38	0.000
	Langmuir	KL (L/mg)	0.06	0.136	0.975
		b (mg/g)	1.57	0.010
Cr	Linear	Kd(L/g)	0.05	0.002	0.962
	Freundlich	Kf (L/g)	0.22	0.006	0.781
		n	2.00	0.001
	Langmuir	KL (L/mg)	0.23	0.188	0.737
		b (mg/g)	1.22	0.029