Study Of Effect Adsorption Of E127 Dye By Iraqi Clay From Aqueous Solution

Abstract

Abstract

The surface of kaolin was diagnosed by an AFM and the results were shown The height of the highest peak reached by a quantity of Kaolin ‎surface is 2.5 µm, the granules, and their diameter with an average diameter of 666.1nm. Using Kaolin's adsorption properties, erythrosine was removed of its aqueous solution. It was determined that the maximal dye adsorption ranged 36.53–40.61%. ‎‎‎‎The results of using the Freundlich, Langmuir, and Temkin adsorption isotherms revealed that at temperatures of (298,308,318) K, the Freundlich model was followed, the Langmuir model did not match, and the Temkin model could only be partially applied. There is also physical adsorption. One of the three kinetic models of the adsorption process that was examined, the pseudo-second-order model, was found to be applicable significantly based on the result. When the thermodynamic functions were computed using the value of the enthalpy, the process was proven to be exothermic, which was negative and equal to (-16.5582 KJ/mol). The entropy ∆°S value, which equaled (-2.2696 J/mole.K), was also negative. Calculating the Gibbs free energy, it was discovered that the process is exothermic adsorption, non-spontaneous, and happens without randomization. ‎‎‎