Adsorption and Thermodynamic Study of Direct Blue 71 Dye on to natural Flint Clay from Aqueous Solution

The remove of direct blue (DB71) anionic dye on flint clay in aqueous solution was investigated by using a batch system for various dye concentrations. The contact time, pH, adsorbent dose, and temperature was studied under batch adsorption technique. The data of adsorption equilibrium fit with isotherm Langmuar and Freiundlich ,when the correlation coefficient used to elucidate the best fitting isotherm model. The thermodynamic parameters such as, ΔHº ,ΔSº and ΔGº. Thermodynamic analysis indicated that the sorption of the dyes onto Flint clay was endothermic and spontaneous.