journal of kerbala university

The extraction of certain pollutant substances from solution on solids is one of the cheapest and easiest separation methods. Furthermore, some of the extracted substances are economically important. In this work, an attempt was done to obtain cheap adsorbent, rice bran, for adsorption and extraction of methylene blue dye (MB) from aqueous solution. Study of some practical parameters affecting adsorption process such as initial dye concentration, acidity, and compute the thermodynamic parameters (ΔHº, ΔGº, ΔSº) for the adsorption process. The extent of the MB removal by rice bran increased with increase in the initial concentration of the dye and temperature. Thermodynamic parameters, such as ΔHº, ΔGº, and ΔSº have been calculated by using the thermodynamic equilibrium coefficient obtained at different temperatures and concentrations were: ΔHº=10.28KJ.mol-1, ΔGº=-5.08KJ.mol-1, ΔSº=52.39J.mol-1.ºK-1. It can be concluded from the results of the present study that the process of adsorption of MB on rice bran may be used effectively to remove the dye from aqueous medium as acidity is increased. The dye removal increased with increase in the initial concentration of the dye and temperature indicating that the process is endothermic and spontaneous. MB can be used to remove the dye even the solution is hot with good efficiency.Keywords: Rice bran, adsorption, methylene blue.