Table 5: Langmuir, Freundlich, and D-R isotherm parameters for sorption of ions onto natural and modified kaolinites.

Isotherm parametersKAHKHKHAK

Langmuir isotherm
(mg·g−1)10.8745.4538.4643.48
(L·g−1)0.70220.31070.29620.2949
0.12460.24350.25240.2532
 ΔG (kJ·mol−1)−24.7−22.7−22.5−22.5
0.97490.97500.95950.9622
Freundlich isotherm
(mg/g)· 1.8518.3673.8236.005
 1/ 0.59590.59820.55500.8171
0.93670.95480.94990.9595
D-R isotherm
(mg·g−1)7.8118.0516.8517.61
(mol2·kJ−2)−2.266−1.723−1.064−1.817
(kJ·mol−1)1.1831.3571.2211.321
0.93530.89090.71780.7878