Table 9.

Desorption ratios of the metal ions from the P (AA/Kry23-DM) SAP ^a and ion diameters (Å) of hydrated of the metal ions (ID) ionic diameters ^b.

Metal Ion	Desorbed Metal Ion (mg)	Sorbed Metal Ion (mg)	Desorption Ratio (%)	ID (Hydrated) (Å)	ID (Å)
Mn2+	0.1125	0.1524	73.8	0.86	1.60
Ni2+	0.1107	0.1687	65.6	0.72	1.34
Cu2+	0.0849	0.1144	74.2	0.62	1.44
Zn2+	0.0536	0.0738	72.7	0.74	1.40
Pb2+	0.0912	0.1066	85.6	1.20	2.42
Cd2+	0.1047	0.1325	79.0	0.96	1.82
Cr3+	0.0880	0.1261	69.8	0.65	1.26
Co3+	0.0748	0.1085	68.9	0.745	0.69
Fe3+	0.0341	0.1436	23.7	0.645	0.63

^a Cavity of the superabsorbent copolymer and is 3.4464 Å (average) [45]. ^b Diameter of H₂O: 2.82 Å [46].