International Science Community Association International Research Journal of Environmental Sciences 2319 - 1414 2 6 2013 May 22 Effect of Various Factors on the Adsorption of Methylene Blue on Silt Fractionated from Bijoypur Soil, Bangladesh 1 7 EN Zaker Y. 1 Department of Chemistry, University of Dhaka, Dhaka-1000, BANGLADESH Hossain M.A. 2 Islam T.S.A. 3 > Research Paper 2013 1 17 2013 May 22 Silt obtained from the fractionation of Bijoypur (Netrokona, Bangladesh) soil having the particle size (53 – 140 µm) was used as an adsorbent for the removal of Methylene Blue (MB) from aqueous solution. The effect of various factors (pH, temperature and adsorbent dose) on adsorption of MB on silt fraction was investigated. The effect of pH shows that the amount adsorbed increased with the increase of pH of solution. The equilibrium adsorption isotherms were analyzed by Langmuir and Freundlich equations. Both Langmuir and Freundlich models can describe theadsorption equilibrium but the Langmuir model shows better agreement. Theamount adsorbed increased with the increase of temperature suggests the formation of dimer in the contact region. SEM micrographs and differential molar isosteric heat of adsorption (H) calculated at different surface coverage, indicate that the surface is heterogeneous having energetically different adsorption sites. Values of n calculated from Freundlich plots indicate that adsorption of MB on silt is spontaneous. At high surface coverage, the differential heat of adsorption versus surface coverage plot shows maximum value indicating the occurrence of structural rearrangement in the adsorbate. With the increase of adsorbent dose, amount adsorbed increased due to the increased surface area of adsorbent. Copyright@ International Science Community Association