Table 4: Thermodynamic data for adsorption on samples AD2, AD3, and NB.

30°C 60°C (kJ mol−1) at 30°C (kJ mol−1) at 60°C (kJ mol−1) (JK−1 mol−1)

AD2 Pb2+0.850.900.41760.27801.82884.66
AD2 Cd2+3.473.39−3.1328−3.3793−0.64318.22
AD2 Zn2+2.722.84−2.5181−2.88931.230312.37
AD3 Pb2+3.102.05−2.8524−1.9828−11.6352−28.99
AD3 Cd2+2.772.21−2.5678−2.1924−6.3587−12.51
AD3 Zn2+3.384.33−3.0678−4.05906.943133.04
NB Pb2+0.460.461.96492.157300.0224−6.41
NB Cd2+3.783.54−3.3474−3.4979−1.82885.01
NB Zn2+2.522.97−2.3259−3.01334.616622.91