Anionic RR120 dye adsorption onto raw clay: Surface properties and adsorption mechanism

► Anionic dye adsorption behavior on raw standard clays and Fouchana clay is compared. ► Fouchana raw clay is composed of kaolinite, smectite and minor illite. ► In our study conditions kaolinite plays a major role in anionic dye adsorption. ► Acidic surface sites and exchangeable Al (III) ions favor the anionic dye adsorption.