Parameters of adsorption isotherms of TC and Cu(ii) on GAC_ox.

Adsorbate	Coexisting compound	Langmuir model			Freundlich model
		Q 0 (mg g−1)	K L (L mg−1)	R 2	K F	1/n	R 2
TC	No	634.0	0.017	0.993	67.4	0.37	0.961
	50 mg L−1 Cu(ii)	691.1	0.040	0.956	122.9	0.32	0.991
	100 mg L−1 Cu(ii)	714.8	0.028	0.970	97.0	0.36	0.988
Cu(ii)	No	117.4	0.169	0.980	40.4	0.25	0.971
	250 mg L−1 TC	131.4	0.203	0.977	43.9	0.27	0.906
	500 mg L−1 TC	126.8	0.240	0.963	43.8	0.27	0.979