Adsorption of a cationic methylene blue dye on an Algerian palygorskite

The capacity of an Algerian Tertiary sedimentary palygorskite to remove methylene blue was studied. The raw material was characterized using X-ray diffraction, infrared spectroscopy, and chemical, granulometric and micotextural analyses. Kinetic experiments were carried out to study the effect of contact time, stirring speed, initial dye concentration and adsorbent mass on the adsorption processes. The palygorskite-rich material mainly consists of this fibrous clay (72%) and calcite (19%) with minor amounts of dolomite (5%), illite (2%) and quartz (2%). After 5 min contact time at room temperature, the adsorption reaction of a 50 mL solution containing 10 ppm of methylene blue on 50 mg of Cal-Pal as adsorbent reached equilibrium, and 97% of cationic dye was fixed. Temperature did not have a significant influence on methylene blue adsorption. The obtained adsorption isotherm indicates high affinity between the adsorbent and the adsorbate. The use of the studied Algerian palygorskite-rich sediment may have great potential for the elimination of textile dyes.