Adsorption of Azo Dye Orange II by Supported TiO2: A Review

The supported TiO2 photocatalyst has been reported for the photodegradation of different organic pollutants. These supported TiO2 photocatalysts include metal and non metal doped TiO2 photocatalysts. The photodegradation can be explained in terms of adsorption. The adsorption of the dye is an significant and obvious parameter in the photodegradation process. The photodegradation is directly related to the adsorbed quantities of the pollutant onto the surface of adsorbant. Adsorption of Orange II, an azo dye has been reported using different adsorbents like fly ash, activated carbon and porous titanium dioxide. This review presents a comparison of maximum adsorption capacities (Qm; mg.g–1) and Langmuir adsorption constant (Kads; L.mg–1) for the adsorbents reported in previous studies.