The study of the adsorption of Malachite green oxalate from aqueous solution was carried out with
activated carbon prepared from Coconut fibre. The Coconut fibre was washed, dried, carbonized, crushed,
sieved and eventually activated at 800oC with 0.1Mol HCl. Adsorption experiment was carried out with various
concentrations of the adsorbate at constant time, temperature, volume and dosage. It was repeated at varying
time, while other influencing factors were kept constant. Finally, the experiment was carried at varying
temperature while other variables were kept constant. The adsorption process fits the Freundlich isotherm with
correlation coefficient of 0.8940. The adsorption also followed the second order kinetic with rate constant of
0.1433, 0.1568 and 0.1570(g/mg.min) at 30, 40 and 50oC respectively. The activation energy under this
condition is 3.80KJ/mol and the thermodynamic parameters: ?Ho = 20.45KJ/mol, ?So = 74.34J/mol.K and the
?Go = -1.49, -2.93, -3.11, -3.37, -3.48 and -3.63J/mol for the various temperatures used. These results affirm the
fact that activated carbon from Coconut fibre has the efficacy of a good adsorbent.