Abideen Idowu Adeogun, Andrew E. Ofudje, A. Idowu Mopelola, O. Kareem Sarafadeen, Equilibrium, Kinetics and Thermodynamic Studies of the Biosorption of Mn (II) Ions from Aqueous Solution by Raw and Acid-Treated Corncob Biomass, Research Journal of Applied Sciences, Volume 6,Issue 5, 2011, Pages 302-309, ISSN 1815-932x, rjasci.2011.302.309, (https://makhillpublications.co/view-article.php?doi=rjasci.2011.302.309) Abstract: Biosorption was carried out in a batch process to test the suitability of corncob for the removal of manganese ion (Mn (II)) from aqueous solution. The amount of metal ions removed from solution depended on the metal ion-substrate contact time, ion concentration, temperature and pH. The adsorption capacity of the biosorbent from corncob was also enhanced by treatment with acid. Kinetic modeling of the data obtained from the study showed that the biosorption of Mn (II) ions by the untreated and acid-treated corncob followed the Largergren pseudo-first order model. The adsorption capacity of the raw biomass is 6.54 mg g-1 while acid treated biomass has adsorption capacity of 7.87 mg g-1. The data obtained from this study fitted well with the Freundlich and Langmuir adsorption isotherms. Keywords: Biosorbent;manganese;kinetics;pseudo-first order and corncob;biomass;Nigeria