Table 13.

The kinetic constants of first-order and second-order for adsorbent (KOH treated).

Conc. (mg/L)	First-order kinetic				Second-order kinetic
	Q e,exp⁡ (mg/g)	K 1∗103 (min−1)	Q e,cal (mg/g)	R 2	Q e,cal (mg/g)	K 2∗103 (g/mg·min)	h (mg/g·min)	R 2
25	4.76	6.49	3.8939	0.98778	5.27	2.23	0.06193	0.9958
50	9.418	6.07	7.5262	0.98794	10.593	1.024	0.1149	0.9939
100	18.65	6.033	15.85	0.96661	20.24	0.540	0.2212	0.9916
150	27.51	5.987	23.36	0.98688	29.152	0.3617	0.3073	0.9913
200	36.44	6.033	32.32	0.9836	37.9836	0.246	0.3549	0.9925
250	45.28	5.941	40.49	0.98846	47.347	0.1733	0.38838	0.9944