Table 3. Isotherm Parameters of NiFe₂O₄-PAC-SH.

Langmuir isotherm
T (K)	Qm	KL	R2	RL	χ2	SSE	RMSE
298	366.3	0.359	0.999	0.027	1.96 × 10–4	7.41 × 10–6	1.21 × 10–3
308	330.0	0.366	0.999	0.026	1.01 × 10–4	4.05 × 10–6	9.0 × 10–4
318	280.9	0.418	0.999	0.023	6.73 × 10–5	7.01 × 10–6	1.18 × 10–3

Freundlich isotherm
T (K)	1/n	KF	R2	χ2	SSE	RMSE
298	0.260	142.4	0.957	2.05 × 10–3	1.14 × 10–2	4.77 × 10–2
308	0.251	133.5	0.950	2.10 × 10–3	1.16 × 10–2	4.81 × 10–2
318	0.226	123.9	0.917	2.71 × 10–3	1.46 × 10–2	5.41 × 10–2

Temkin isotherm
T (K)	bT	KT	R2	χ2	SSE	RMSE
298	40.01	7.61	0.988	0.706	197.21	6.28
308	45.50	7.92	0.978	0.921	245.04	7.00
318	58.24	11.22	0.948	1.603	362.33	8.51

Dubinin–Radushkevich isotherm
T (K)	qmax	E	R2	χ2	SSE	RMSE
298	308.9	8.99	0.897	4.81 × 10–3	2.73 × 10–2	7.34 × 10–2
308	287.1	8.28	0.905	3.94 × 10–3	2.21 × 10–2	6.64 × 10–2
318	252.8	8.01	0.941	1.93 × 10–3	1.06 × 10–2	4.60 × 10–2