Adsorption rate parameters for the pseudo-first and pseudo-second-order models.

Adsorbate	Coexisting compound	Pseudo-first-order model		Pseudo-second-order model
		k 1 (h−1)	R 2	k 2 (g mg−1 × h)	R 2
TC	No	0.058	0.979	0.065	0.994
	50 mg L−1 Cu(ii)	0.018	0.994	0.007	0.993
	100 mg L−1 Cu(ii)	0.017	0.992	0.008	0.992
Cu(ii)	No	0.312	0.993	0.246	0.986
	250 mg L−1 TC	0.035	0.984	0.030	0.993
	500 mg L−1 TC	0.019	0.980	0.016	0.974