Effect of Surface Area, Micropores, Secondary Micropores, and Mesopores Volumes of Activated Carbons on Reactive Dyes Adsorption from Solution

The ability of six activated carbons to remove the problematic reactive dyes from textile solution was correlated to their physical characteristics. Specific surface area, micro‐, meso‐, and total volume were established using the Braunnaur, Emmet, and Teller (BET) and Dubinin–Radushkevich (D–R) equations. According to the N2 adsorption method, five of the carbons exhibited type I adsorption characteristics with one carbon showing a type III isotherm. Activated carbon Filtrasorb 400 outperformed the carbons under investigation by showing the presence of advanced primary and secondary micropores. A poor linear correlation between carbon surface area and performance was found. Adsorption properties of carbons were better related to their pore volumes. It was found that secondary micropore volume of carbons (0.8 nm < D secondary micropore < 2 nm) has an important role in reactive dyes adsorption.