Decontamination of cadmium(II) from synthetic wastewater onto shea fruit shell biomass

Abstract

Shea fruit shells being an agricultural waste material was utilized to test its novelty as an inexpensive biosorbent for the elimination of Cd(II) from synthetic wastewater using the batch method. A batch study was employed to probe the impact of pH of the solution, contact time, temperature and initial concentration on the depollution of Cd(II) ions using unmodified Shea fruit shells biomass. The decontamination of Cd(II) by the unmodified Shea fruit shells biomass was found to be dependent on these adsorption parameters. The equilibrium data best represented Freundlich isotherm by a correlation coefficient (R2) of 0.9691. The kinetic models analyzed suggest pseudo-second-order (R2= 0.9515 ) as the best fit model signifying that the removal of Cd(II) ions was on account of chemisorption. The positive values of the thermodynamic parameters, ΔH° and ΔS° reveal endothermic and increase of disorder of the process while the negative charge of ΔG° shows spontaneity of the system.