Decolorization Kinetics and Thermodynamics of Auramine Lake Yellow O on Expanded Graphite Loaded with Titania

In order to investigate the decolorization characteristics of expanded graphite (EG) loaded with titania for auramine lake yellow O adsorbate, the adsorbent is prepared with 50 mesh natural graphite as raw materials, potassium permanganate as oxidant and vitriol, tetranbutyl titanate as intercalation compound. The expanded volume of EG loaded with titania is 320 mL/g. We detect the equilibration time, influence of ionic strength and initial concentration of the adsorbate on decolorization rate. Based on pseudo first-order and second-order kinetic model, the decolorization model is discussed. Decolorization rate and activation energy were calculated. Studies show that decolorization rate of EG loaded with titania for auramine lake yellow O decrease with the increase of the adsorbate initial concentration and increase with the increase of ionic strength; the decolorization process can be well described by the pseudo second-order kinetic model; decolorization equilibrium time and half decolorization time decrease with the increase of temperature.