In this study, sorption experiments of the Cu (II) ion onto raw
corn cob, raw corn stalk and corn stalk oxidized with nitric acid were used for the removal of this metal ion from aqueous
solutions. The sorption behavior of copper ions in these experiments
with various adsorbents was examined and the following
conclusions can be made.
1. It was observed that RCC, in this study, had a higher uptake
capacity than RCS, but lower than MCS for Cu (II) ion.
2. It was found that adsorption capacity of corn stalk increased
from 0.113 to 0.325 mmol g1 after modification.
3. The Freundlich isotherm model is appropriate to describe the
sorption of the Cu (II) ion on the raw corn cob and it has a better
fit than the Langmuir isotherm model. In contrast, the higher R2
values for RCS and MCS showed that the Langmuir isotherm
exhibited a better fit to the adsorption data than the Freundlich
isotherm.