Details of the isotherm constants determined for various adsorption isotherm models for the adsorption process of 2,4-DCP and 2,4-DNP on the adsorbent Fe₃O₄@AC–SS.

Analyte	Parameters	Temperature
		298 K	313 K	333 K	343 K	353 K
Langmuir
2,4-DCP	q m (mg g−1)	98.0392	84.8176	89.2857	73.5294	52.083
	b (L mg−1)	0.0123	0.0196	0.0113	0.0122	0.0154
	R 2	0.9504	0.9017	0.7081	0.8770	0.9085
	R L	0.5066	0.4591	0.5953	0.5774	0.5204
2,4-DNP	q m (mg g−1)	46.0829	49.7512	43.4783	26.9542	14.8588
	b (L mg−1)	0.0894	0.0435	0.0440	0.4294	0.0360
	R 2	0.7851	0.9089	0.7727	0.9302	0.9595
	R L	0.1572	0.2772	0.2749	0.2796	0.3166
Freundlich
2,4-DCP	K F ((mg g−1) (L mg−1)1/n)	1.8425	2.0086	1.2075	1.0607	0.9513
	N	1.1942	1.3002	1.1435	1.1368	1.1482
	1/n	0.8374	0.7691	0.8745	0.8797	0.8709
	R 2	0.9998	0.9988	0.9976	0.9995	0.9994
2,4-DNP	K F ((mg g−1) (L mg−1)1/n)	3.9201	2.3823	2.1188	1.4876	0.7125
	N	1.6234	1.3583	1.3405	1.3454	1.2404
	1/n	0.6160	0.7362	0.7460	0.7433	0.8062
	R 2	0.9719	0.9929	0.9815	0.9971	0.9977
Temkin
2,4-DCP	K T (L mg−1)	0.4153	0.4750	0.3097	0.3050	0.2770
	b T (kJ mol−1)	210.3738	265.7966	261.7283	244.3827	316.8486
	R 2	0.9227	0.9178	0.9140	0.9338	0.9294
2,4-DNP	K T (L mg−1)	0.8824	0.5176	0.4667	0.3348	0.2011
	b T (kJ mol−1)	269.7617	253.6584	274.6317	320.2576	406.0323
	R 2	0.9078	0.9417	0.9478	0.9195	0.9295
Dubinin–Radushkevich (D–R)
2,4-DCP	q m (mg g−1)	22.7031	20.1600	19.6465	18.6156	17.1124
	β (mol2 kJ−2)	2.7610	1.9817	3.5910	4.3731	4.2337
	R 2	0.7825	0.7666	0.7766	0.7747	0.7700
	E	1.2036	1.4207	1.0554	0.9564	0.9720
2,4-DNP	q m (mg g−1)	21.8106	21.5118	20.6559	17.6547	13.6031
	β (mol2 kJ−2)	0.7336	1.6375	1.7332	2.8632	8.2548
	R 2	0.6595	0.7383	0.7288	0.7207	0.7877
	E	2.3351	1.5629	1.5192	1.1820	0.6961
Halsey
2,4-DCP	N	−1.1942	−1.3000	−1.1435	−1.1368	−1.1423
	K	0.4821	0.4038	0.8060	0.9352	1.0591
	R 2	0.9998	0.9988	0.9976	0.9995	0.9994
2,4-DNP	N	−1.6234	−1.3583	−1.3405	−0.1345	−1.2404
	K	0.4311	0.5278	0.5712	0.7443	0.2732
	R 2	0.9719	0.9929	0.9815	0.9971	0.9977