Biosorption of cadmium ions from solution by coconut copra
meal is a spontaneous and exothermic process. The saturated
monolayer biosorption capacity of the copra meal for cadmium
ions at 299K was calculated to be 4.99 mg/g. The biosorption
process is pH dependent and maximum removal of cadmium
from aqueous solution occurred at pH 6. Non-linear method of
error analysis could be a better way to compare isotherm fitting.
Langmuir isotherm is a special case of Redlich–Peterson
isotherm when constant g is unity. Both two-parameter Langmuir
and three-parameter Redlich–Peterson isotherms were the
best-fitting models for the biosorption of cadmium on coconut
copra meal.