Equilibrium data, kinetics and process design for the adsorptive removal of safranin-o by activated carbons

Abstract The impact of pH, contact time and temperature of solution on the adsorptive removal of Safranin-O by activated carbons with variable number of carbon–oxygen functional groups and unlike surface characteristics have been studied. The experimental adsorption data have been studied with Langmuir and Freundlich isotherms. The data fit the Langmuir equation better. The adsorption is much affected by the number of acidic groups. It increases on increasing the acidic functional groups by oxidation and decreases slowly on the removal of surface groups during degassing. The adsorption obeys the first-order rate law. In single batch adsorber design, the prediction has been done that the required amount of oxidized activated carbon is 56% less than that of the unoxidized activated carbon for 95% removal of Safranin-O from its solution.