Mathematical models parameters Pb(II) Langmuir isotherm R2 KL× 102 qm(mg/g) 0.820 12.73 18.51 Freundlich isotherm R2 KF n 0.816 104.2×10-4 1.225 Temkin isotherm R2 B1 KT 0.926 37.97 155.0 D-R isotherm R2 Β ×104 qm (mg/g) ×10-4 E kJ/mol 0.987 5 13.74 31.6×10-2 Jovanoic isotherm R2 KJ (L/mg) qm(mg/g) 0.912 0.056 4.862

Table 4: Different adsorption isotherm model parameters for the adsorption of Pb(II) on PFSR.