Phenol Red Adsorption from Aqueous Solution on the Modified Bentonite

Table 3

The parameters of isotherm models in linear form for the adsorption of phenol red onto the modified bentonite.

CB
T (K)	Langmuir model			Freundlich model				D-R model
	qm (mg·g^−1)	KL (L·mg^−1)	R^2	RL	KF (mg·g^−1)	n	R^2	E (kJ·mol^−1)	R^2
293	156.3	0.185	0.964	0.211–0.752	49.95	3.01	0.808	13.95	0.932
303	166.7	0.278	0.983	0.167–0.782	93.04	8.19	0.784	15.97	0.952
313	169.4	0.625	0.998	0.098–0.535	80.16	4.22	0.897	17.86	0.913
AlCB
T (K)	Langmuir model			Freundlich model			D-R model
	qm (mg·g^−1)	KL (L·mg^−1)	R^2	RL	KF (mg·g^−1)	n	R^2	E (kJ·mol^−1)	R^2
293	71.4	0.23	0.979	0.316–0.725	30.60	1.93	0.969	11.46	0.974
303	125.0	0.62	0.959	0.017–0.040	46.99	2.58	0.787	14.11	0.943
313	142.9	0.82	0.956	0.111–0.373	35.91	4.59	0.701	18.74	0.695
FeCB
T (K)	Langmuir model			Freundlich model			D-R model
	qm (mg·g^−1)	KL (L·mg^−1)	R^2	RL	KF (mg·g^−1)	n	R^2	E (kJ·mol^−1)	R^2
293	90.9	0.77	0.996	0.073–0.191	55.31	6.45	0.885	21.83	0.969
303	100.0	0.61	0.987	0.028–0.313	31.12	2.90	0.856	13.62	0.868
313	110.1	0.56	0.993	0.040–0.400	51.42	5.46	0.810	21.71	0.998