Table 4 Parameters of the Langmuir, Freundlich and Sips isotherm model.

From: Rare Earth Elements Removal from Water Using Natural Polymers

  Langmuir isotherm
q m,exp (mg/g) K L (L/mg) q L (mg/g) R 2
Eu (III) 32 0.052 32.27 0.9914
Nd (III) 73 0.17 80.07 0.9981
  Freundlich isotherm
  K F (mg/g) 1/ n F R 2
Eu (III) 5.24 0.34 0.9190
Nd (III) 21.17 0.30 0.8825
  Sips isotherm
  K s q s (mg/g) 1/ n s R 2
Eu (III) 0.05 32.09 1.01 0.9897
Nd (III) 0.16 78.30 1.07 0.9985