Removal of Ammonium from Aqueous Solutions Using Zeolite Synthesized from Electrolytic Manganese Residue

Table 2

Isotherm constants and regression data of adsorption isotherms of ammonium on EMRZ at different temperatures (EMRZ dosage = 0.2 g/100 mL; contact time = 100 min; pH value = 8.0).

Adsorption isotherm	Temperature (°C)
	25	30	35
Langmuir isotherm	KL = 0.0205	KL = 0.02653	KL = 0.03354
	q0 = 31.08	q0 = 32.05	q0 = 32.88
	R^2 = 0.9699	R^2 = 0.9856	R^2 = 0.9886
Freundlich isotherm	KF = 3.2318	KF = 4.1460	KF = 5.4319
	1/n = 0.3978	1/n = 0.3602	1/n = 0.3288
	R^2 = 0.9916	R^2 = 0.9996	R^2 = 0.9988
Koble–Corrigan isotherm	a = 3.6079	a = 4.3106	a = 5.3322
	b = −0.2311	b = −0.0246	b = 0.0161
	n = 0.1927	n = 0.3261	n = 0.3498
	R^2 = 0.9945	R^2 = 0.9990	R^2 = 0.9974
Temkin isotherm	AT = 0.2058	AT = 0.2891	AT = 0.4187
	BT = 6.799	BT = 6.559	BT = 6.668
	R^2 = 0.9582	R^2 = 0.9840	R^2 = 0.9805
Dubinin–Radushkevich isotherm	Qm = 21.5176	Qm = 22.8728	Qm = 25.2824
	K = 6.9309 × 10^−5	K = 5.4558 × 10^−5	K = 3.8141 × 10^−5
	R^2 = 0.7579	R^2 = 0.8200	R^2 = 0.8297