Zeolite Application in Wastewater Treatment

Table 4

Selectivity in competitive adsorption of heavy metals by different zeolites.

Adsorption selectivity			Ionic properties
Zeolite	Selectivity	References	Heavy metal	Hydrated radius (Å)	Unhydrated radius (Å)	Free energy of hydration (kJ·mol^-1)	References
FAU-type	Pb^2+>Cu^2+>Cd^2+>Zn^2+>Co^2+	[164]	Pb	4.01	1.32	-1425	[165, 166]
A	Cu^2+>Cr^3+>Zn^2+>Co^2+>Ni^2+	[82]	Cu	4.19	0.72	-2010
A	Pb^2+>Cd^2+>Cu^2+>Zn^2+>Ni^2+	[83]	Cd	4.26	0.97	-1755
A	Pb^2+>Cd^2+>Zn^2+>Ni^2+>Cu^2+	[148]	Zn	4.30	0.74	-1955
NaP1	Cr^3+>Cu^2+>Zn^2+>Cd^2+>Ni^2+	[74]	Co	4.23	0.72	-1915
X	Pb^2+>Cd^2+>Cu^2+>Zn^2+>Ni^2+	[83]	Cr	4.61	0.64	-4010
X	Cr^3+>Cu^2+>Cd^2+>Zn^2+	[115]	Ni	4.04	0.70	-1980
Scolecite	Cr^3+>Mn^2+>Cd^2+>Ni^2+	[73]	Mn	4.38	0.80	-1760
Clinoptilolite	Pb^2+>Zn^2+>Cu^2+>Cd^2+	[81]
Clinoptilolite	Cu^2+>Cr^3+>Zn^2+>Cd^2+>Ni^2+	[74]