Kinetic and Thermodynamic Studies of Chromium Ion Adsorption Using Chitosan from Mussel Shell

Abstract

A study was carried out to investigate the removal of chromium (VI) ion from chromate solution using deacetylated chitin extracted from mussel shell. Mussel shells were obtained from Gubi dam in Bauchi, Nigeria and chemical method was used to extract chitin and then chitosan from these shells. A batch adsorption study was used to generate data for kinetic modelling. Out of the four kinetic models tested, the adsorption process was found to follow the pseudo-second order kinetic model with an R²-value of 0.9997; The process was physical with a free sorption energy of 0.224 kJ/mol. Also, the enthalpy of adsorption was -67.295 kJ/mol K and the Gibbs free energies were all negative, thus the process is spontaeneous and exothermic.

Keywords: Kinetic, Chitosan, Mussel, Chromium, Adsorption, Thermodynamic