COMPARATIVE STUDY OF THE ADSORPTION OF MAIZE STARCH AND CASSAVA STARCH ONTO HAEMATITE

The interaction of maize starch and cassava starch with natural haematite was investigated through adsorption studies. The adsorption density was found to vary with pH, with the maximum adsorption taking place between pH 4 and pH 9.5. The adsorption process followed Langmuir-type isotherm at the average temperature of 30°C. Adsorption process is feasible and maximum monolayer adsorption capacity was found to be 1428.6 mg.m-2 for both starches. The mean adsorption free energy was -28.0 kJ.mol-1. The negative value of G confirms the feasibility of the process and the magnitudes indicate evidence of possible involvement of chemical interaction and hydrophobic association and/or van der Waal’s attraction forces in the adsorption process.