Methylene blue and Congo red removal by activated carbons: A current literature

Dye is a major source of water pollution. This mini-review highlights the origin of dye, its removal strategies, and the recent literature of methylene blue and Congo red adsorption by activated carbons. Adsorption is a unique process that relies upon the physicochemical properties of the activated carbon and the inherent characteristics of dye. Also, factors affecting adsorption, such as contact time, temperature, and concentration, were discussed to gain insight into dye removal mechanisms.