Table 2.

Kinetic models parameters and correlation coefficients (R²) for desorption of PHE at various initial PHE concentration

Kinetic models	Kinetic parameters	Initial PHE concentration,C0(mg kg−1)
		400	800	1200	1600
	qe, exp(mg kg−1)	185.49	326.1	475.77	563.1
Pseudo-first order	k1 (min−1)	0.073	0.072	0.067	0.071
	qe (mg kg−1)	149.306	134.29	113.295	222.516
	R2	0.928	0.896	0.841	0.767
Pseudo-second order
Type (I)	k2p (kg mg−1 min−1)	8.06 × 10−4	0.0005	0.0013	3.33 × 10−4
	qe(mg kg−1)	200	500	500	1000
	R2	0.997	0.998	0.999	0.996
Type (II)	k2p(kg mg−1 min−1)	0.001	0.000333	0.002	0.0005
	qe (mg kg−1)	200	500	500	1000
	R2	0.977	0.917	0.962	0.770
Type (III)	k2p(kg mg−1 min−1)	1.036 × 10−3	0.000791	0.00149	0.001554
	qe (mg kg−1)	192.4	350.4	482.88	545.9
	R2	0.952	0.794	0.942	0.727
Type (IV)	k2p(kg mg−1 min −1)	9.759 × 10−4	0.000599	0.00139	0.001096
	qe (mg kg−1)	194.68	376.5	485.524	562.013
	R2	0.952	0.794	0.942	0.727
Fractional power	k (mg kg−1 min -v)	69.13	159.6526	342.0647	393.8618
	v	0.24	0.189	0.083	0.082
	R2	0.980	0.727	0.839	0.853