The adsorption of metal ions at different pH values.

Amount of metal ions adsorbed [qe (mmol g−1)] for different metals	pH of the medium
	2	3	4	5	6	7
Cu2+	0.74	1.0	2.38	3.72	3.3	2.11
Pb2+	0.40	0.7	1.21	2.35	2.48	1.82
Cr3+	0.37	0.61	1.17	1.61	2.41	1.78
Cd2+	0.28	0.43	0.76	0.81	1.2	0.74