Adsorption of Mixture of Two Dyes on Activated Carbon

Activated carbon is known as adsorbent to various contaminants from wastewater and air. The aim of work was to estimate sorptive capacity of activated carbon in the removal of dyes, which are contaminants from textile wastewaters. The mixture of two dyes, methyl blue and naphtol green B were chosen to study, and as adsorbent we have chosen the activated carbon WDex, virgin and regenerated. Dye concentration in both cases was 200 mg/dm. Sorption abilities of activated carbon were expressed by mass balance relationship in case of fresh activated carbon it was 60 mg/g, and after regeneration from 8 to 13 mg/g. The experimental data adsorption isotherms were defined and adsorption theoretical model such as Freundlich or Langmuir, was selected. The highest removal efficiency in case of methyl blue was 94% for virgin carbon, the lowest 75% (carbon after 4 regeneration). The highest removal efficiency in case of naphtol green B was 78% for carbon after IV regeneration, the lowest 55% (carbon after 1 regeneration). The experimental data shows that activated carbon can be used for the decontamination of dyes from textile wastewater. However, model tests need to be verified on real wastewater samples.