Parameters of the Langmuir and Freundlich isotherm models fitted using the copper ion adsorption on coal fly ash data^a.

Langmuir Model				Freundlich Model
q m (mg L−1)	k L (L mg−1)	R 2	q m,exp (mg g−1)	k F (mg−1/n L−1/n g−1)	n	R 2
56.8	2.81	0.99	58.2	21.1	2.42	0.92

^a q _m,exp (mg g⁻¹) represents the maximum amount of adsorbed copper ions obtained from the experiment.